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NAME

       xorg.conf and xorg.conf.d - configuration files for Xorg X server

INTRODUCTION

       Xorg  supports several mechanisms for supplying/obtaining configuration
       and run-time parameters: command line options,  environment  variables,
       the  xorg.conf and xorg.conf.d configuration files, auto-detection, and
       fallback defaults. When the same information is supplied in  more  than
       one  way,  the  highest  precedence  mechanism  is  used.  The  list of
       mechanisms is ordered from highest precedence to lowest. Note that  not
       all  parameters  can be supplied via all methods. The available command
       line  options  and  environment  variables  (and  some  defaults)   are
       described   in   the   Xserver(1)   and   Xorg(1)  manual  pages.  Most
       configuration file  parameters,  with  their  defaults,  are  described
       below.   Driver   and  module  specific  configuration  parameters  are
       described in the relevant driver or module manual page.

DESCRIPTION

       Xorg uses a configuration file called xorg.conf and files ending in the
       suffix .conf from the directory xorg.conf.d for its initial setup.  The
       xorg.conf configuration file is searched for in  the  following  places
       when the server is started as a normal user:

           /etc/X11/<cmdline>
           /usr/etc/X11/<cmdline>
           /etc/X11/$XORGCONFIG
           /usr/etc/X11/$XORGCONFIG
           /etc/X11/xorg.conf-4
           /etc/X11/xorg.conf
           /etc/xorg.conf
           /usr/etc/X11/xorg.conf.<hostname>
           /usr/etc/X11/xorg.conf-4
           /usr/etc/X11/xorg.conf
           /usr/lib/X11/xorg.conf.<hostname>
           /usr/lib/X11/xorg.conf-4
           /usr/lib/X11/xorg.conf

       where  <cmdline> is a relative path (with no ".." components) specified
       with the -config command line option, $XORGCONFIG is the relative  path
       (with  no  ".." components) specified by that environment variable, and
       <hostname> is the machine's hostname as reported by gethostname(3).

       When the Xorg server is started by the "root"  user,  the  config  file
       search locations are as follows:

           <cmdline>
           /etc/X11/<cmdline>
           /usr/etc/X11/<cmdline>
           $XORGCONFIG
           /etc/X11/$XORGCONFIG
           /usr/etc/X11/$XORGCONFIG
           /etc/X11/xorg.conf-4
           /etc/X11/xorg.conf
           /etc/xorg.conf
           /usr/etc/X11/xorg.conf.<hostname>
           /usr/etc/X11/xorg.conf-4
           /usr/etc/X11/xorg.conf
           /usr/lib/X11/xorg.conf.<hostname>
           /usr/lib/X11/xorg.conf-4
           /usr/lib/X11/xorg.conf

       where  <cmdline>  is  the  path specified with the -config command line
       option (which may be absolute or relative),  $XORGCONFIG  is  the  path
       specified by that environment variable (absolute or relative), $HOME is
       the path specified by  that  environment  variable  (usually  the  home
       directory),  and  <hostname>  is  the machine's hostname as reported by
       gethostname(3).

       Additional configuration  files  are  searched  for  in  the  following
       directories when the server is started as a normal user:

           /etc/X11/<cmdline>
           /etc/X11/<cmdline>
           /etc/X11/xorg.conf.d
           /etc/X11/xorg.conf.d

       where  <cmdline> is a relative path (with no ".." components) specified
       with the -configdir command line option.

       When the Xorg  server  is  started  by  the  "root"  user,  the  config
       directory search locations are as follows:

           <cmdline>
           /etc/X11/<cmdline>
           /etc/X11/<cmdline>
           /etc/X11/xorg.conf.d
           /etc/X11/xorg.conf.d

       where  <cmdline> is the path specified with the -configdir command line
       option (which may be absolute or relative).

       Finally, configuration files will also be searched for  in  directories
       reserved for system use. These are to separate configuration files from
       the vendor or 3rd party packages from those  of  local  administration.
       These files are found in the following directories:

           /usr/share/X11/xorg.conf.d
           /usr/share/X11/xorg.conf.d

       The  xorg.conf  and  xorg.conf.d  files  are  composed  of  a number of
       sections which may be present in any order, or omitted to  use  default
       configuration values.  Each section has the form:

           Section  "SectionName"
               SectionEntry
               ...
           EndSection

       The section names are:

           Files          File pathnames
           ServerFlags    Server flags
           Module         Dynamic module loading
           Extensions     Extension enabling
           InputDevice    Input device description
           InputClass     Input class description
           Device         Graphics device description
           VideoAdaptor   Xv video adaptor description
           Monitor        Monitor description
           Modes          Video modes descriptions
           Screen         Screen configuration
           ServerLayout   Overall layout
           DRI            DRI-specific configuration
           Vendor         Vendor-specific configuration

       The   following   obsolete  section  names  are  still  recognised  for
       compatibility purposes.  In new config files, the  InputDevice  section
       should be used instead.

           Keyboard       Keyboard configuration
           Pointer        Pointer/mouse configuration

       The old XInput section is no longer recognised.

       The ServerLayout sections are at the highest level.  They bind together
       the input and output devices that will be used in a session.  The input
       devices  are  described  in  the  InputDevice sections.  Output devices
       usually consist of multiple independent components  (e.g.,  a  graphics
       board  and a monitor).  These multiple components are bound together in
       the Screen sections, and  it  is  these  that  are  referenced  by  the
       ServerLayout  section.   Each  Screen section binds together a graphics
       board and a monitor.  The graphics boards are described in  the  Device
       sections, and the monitors are described in the Monitor sections.

       Config  file  keywords  are  case-insensitive,  and  "_" characters are
       ignored.   Most  strings  (including  Option  names)  are  also   case-
       insensitive, and insensitive to white space and "_" characters.

       Each  config  file  entry  usually  takes up a single line in the file.
       They consist of a keyword, which is possibly followed by  one  or  more
       arguments,  with the number and types of the arguments depending on the
       keyword.  The argument types are:

           Integer     an integer number in decimal, hex or octal
           Real        a floating point number
           String      a string enclosed in double quote marks (")

       Note: hex integer values must be prefixed with "0x", and  octal  values
       with "0".

       A  special  keyword called Option may be used to provide free-form data
       to various components of the server.  The Option keyword  takes  either
       one  or  two  string  arguments.  The first is the option name, and the
       optional second argument is  the  option  value.   Some  commonly  used
       option value types include:

           Integer     an integer number in decimal, hex or octal
           Real        a floating point number
           String      a sequence of characters
           Boolean     a boolean value (see below)
           Frequency   a frequency value (see below)

       Note  that  all  Option  values,  not just strings, must be enclosed in
       quotes.

       Boolean options may optionally have a value specified.  When  no  value
       is specified, the option's value is TRUE.  The following boolean option
       values are recognised as TRUE:

           1, on, true, yes

       and the following boolean option values are recognised as FALSE:

           0, off, false, no

       If an option name is prefixed with  "No",  then  the  option  value  is
       negated.

       Example: the following option entries are equivalent:

           Option "Accel"   "Off"
           Option "NoAccel"
           Option "NoAccel" "On"
           Option "Accel"   "false"
           Option "Accel"   "no"

       Frequency  option  values  consist  of a real number that is optionally
       followed by one of the following frequency units:

           Hz, k, kHz, M, MHz

       When the unit name is omitted, the correct  units  will  be  determined
       from  the  value  and  the expectations of the appropriate range of the
       value.  It is recommended that the units always be specified when using
       frequency option values to avoid any errors in determining the value.

FILES SECTION

       The  Files  section  is used to specify some path names required by the
       server.  Some of these paths can also be set from the command line (see
       Xserver(1) and Xorg(1)).  The command line settings override the values
       specified in the config file.  The Files section is  optional,  as  are
       all of the entries that may appear in it.

       The entries that can appear in this section are:

       FontPath "path"
              sets  the search path for fonts.  This path is a comma separated
              list of font path elements which the Xorg  server  searches  for
              font databases.  Multiple FontPath entries may be specified, and
              they will be concatenated to build up the fontpath used  by  the
              server.   Font  path  elements  can be absolute directory paths,
              catalogue directories or a font server identifier.  The  formats
              of the later two are explained below:

              Catalogue directories:

                  Catalogue  directories  can  be  specified  using the prefix
                  catalogue: before the directory name. The directory can then
                  be  populated  with  symlinks  pointing  to  the  real  font
                  directories, using the following syntax in the symlink name:

                      <identifier>:[attribute]:pri=<priority>

                  where    <identifier>   is   an   alphanumeric   identifier,
                  [attribute] is an attribute which  will  be  passed  to  the
                  underlying  FPE and <priority> is a number used to order the
                  fontfile FPEs. Examples:

                      75dpi:unscaled:pri=20 -> /usr/share/X11/fonts/75dpi
                      gscript:pri=60 -> /usr/share/fonts/default/ghostscript
                      misc:unscaled:pri=10 -> /usr/share/X11/fonts/misc

              Font server identifiers:

                  Font server identifiers have the form:

                      <trans>/<hostname>:<port-number>

                  where <trans> is the transport type to use to connect to the
                  font server (e.g., unix for UNIX-domain sockets or tcp for a
                  TCP/IP  connection),  <hostname>  is  the  hostname  of  the
                  machine  running  the  font server, and <port-number> is the
                  port number that the font server is  listening  on  (usually
                  7100).

              When  this entry is not specified in the config file, the server
              falls back to the compiled-in default font path, which  contains
              the  following  font  path  elements  (which can be set inside a
              catalogue directory):

                  /usr/share/fonts/X11/misc/
                  /usr/share/fonts/X11/TTF/
                  /usr/share/fonts/X11/OTF/
                  /usr/share/fonts/X11/Type1/
                  /usr/share/fonts/X11/100dpi/
                  /usr/share/fonts/X11/75dpi/

              Font path elements that are found to be invalid are removed from
              the font path when the server starts up.

       ModulePath "path"
              sets  the  search  path  for loadable Xorg server modules.  This
              path is a comma separated list of  directories  which  the  Xorg
              server  searches  for  loadable  modules  loading  in  the order
              specified.  Multiple ModulePath entries may  be  specified,  and
              they  will  be concatenated to build the module search path used
              by the server.  The default module path is

                  /usr/lib/xorg/modules

       XkbDir "path"
              sets the base directory for keyboard layout files.  The  -xkbdir
              command  line  option can be used to override this.  The default
              directory is

                  /usr/share/X11/xkb

SERVERFLAGS SECTION

       In addition to options specific to this section (described below),  the
       ServerFlags section is used to specify some global Xorg server options.
       All  of  the  entries  in  this  section  are  Options,  although   for
       compatibility  purposes  some  of  the  old  style  entries  are  still
       recognised.  Those old style entries are not documented here, and using
       them  is  discouraged.  The ServerFlags section is optional, as are the
       entries that may be specified in it.

       Options  specified  in  this  section  (with  the  exception   of   the
       "DefaultServerLayout" Option) may be overridden by Options specified in
       the active ServerLayout section.  Options with command line equivalents
       are overridden when their command line equivalent is used.  The options
       recognised by this section are:

       Option "DefaultServerLayout"  "layout-id"
              This specifies the default ServerLayout section to  use  in  the
              absence of the -layout command line option.

       Option "NoTrapSignals"  "boolean"
              This   prevents  the  Xorg  server  from  trapping  a  range  of
              unexpected fatal signals and exiting cleanly.  Instead, the Xorg
              server  will  die  and  drop core where the fault occurred.  The
              default behaviour is for the Xorg server to  exit  cleanly,  but
              still  drop  a core file.  In general you never want to use this
              option unless you are debugging an Xorg server problem and  know
              how to deal with the consequences.

       Option "UseSIGIO"  "boolean"
              This  controls whether the Xorg server requests that events from
              input devices be reported via a SIGIO signal handler (also known
              as SIGPOLL on some platforms), or only reported via the standard
              select(3) loop.  The default  behaviour  is  platform  specific.
              In  general  you  do  not want to use this option unless you are
              debugging the Xorg server, or  working  around  a  specific  bug
              until it is fixed, and understand the consequences.

       Option "DontVTSwitch"  "boolean"
              This  disallows  the  use  of the Ctrl+Alt+Fn sequence (where Fn
              refers to one of the numbered function keys).  That sequence  is
              normally  used  to  switch  to  another  "virtual  terminal"  on
              operating systems that have this feature.  When this  option  is
              enabled,  that key sequence has no special meaning and is passed
              to clients.  Default: off.

       Option "DontZap"  "boolean"
              This disallows  the  use  of  the  Terminate_Server  XKB  action
              (usually on Ctrl+Alt+Backspace, depending on XKB options).  This
              action is normally used to terminate the Xorg server.  When this
              option is enabled, the action has no effect.  Default: off.

       Option "DontZoom"  "boolean"
              This   disallows   the   use  of  the  Ctrl+Alt+Keypad-Plus  and
              Ctrl+Alt+Keypad-Minus sequences.  These sequences allows you  to
              switch  between video modes.  When this option is enabled, those
              key sequences have no special meaning and are passed to clients.
              Default: off.

       Option "DisableVidModeExtension"  "boolean"
              This  disables  the  parts  of the VidMode extension used by the
              xvidtune client that can be used  to  change  the  video  modes.
              Default: the VidMode extension is enabled.

       Option "AllowNonLocalXvidtune"  "boolean"
              This  allows the xvidtune client (and other clients that use the
              VidMode extension) to connect from another host.  Default:  off.

       Option "AllowMouseOpenFail"  "boolean"
              This  tells the mousedrv(4) and vmmouse(4) drivers to not report
              failure if the mouse device can't be opened/initialised.  It has
              no  effect  on  the  evdev(4)  or  other  drivers.  The previous
              functionality of allowing the server to start  up  even  if  the
              mouse  device  can't be opened/initialised is now handled by the
              AllowEmptyInput option.  Default: false.

       Option "VTSysReq"  "boolean"
              enables the SYSV-style VT switch sequence for  non-SYSV  systems
              which support VT switching.  This sequence is Alt-SysRq followed
              by a function key (Fn).  This prevents the Xorg server  trapping
              the  keys  used  for the default VT switch sequence, which means
              that clients can access them.  Default: off.

       Option "BlankTime"  "time"
              sets  the  inactivity  timeout  for  the  blank  phase  of   the
              screensaver.   time  is  in  minutes.  This is equivalent to the
              Xorg server's -s flag, and the value can be changed at  run-time
              with xset(1).  Default: 10 minutes.

       Option "StandbyTime"  "time"
              sets  the inactivity timeout for the standby phase of DPMS mode.
              time is in minutes, and the value can  be  changed  at  run-time
              with  xset(1).   Default: 10 minutes.  This is only suitable for
              VESA DPMS compatible monitors, and may not be supported  by  all
              video  drivers.   It  is  only enabled for screens that have the
              "DPMS" option set (see the MONITOR section below).

       Option "SuspendTime"  "time"
              sets the inactivity timeout for the suspend phase of DPMS  mode.
              time  is  in  minutes,  and the value can be changed at run-time
              with xset(1).  Default: 10 minutes.  This is only  suitable  for
              VESA  DPMS  compatible monitors, and may not be supported by all
              video drivers.  It is only enabled for  screens  that  have  the
              "DPMS" option set (see the MONITOR section below).

       Option "OffTime"  "time"
              sets  the  inactivity  timeout  for  the off phase of DPMS mode.
              time is in minutes, and the value can  be  changed  at  run-time
              with  xset(1).   Default: 10 minutes.  This is only suitable for
              VESA DPMS compatible monitors, and may not be supported  by  all
              video  drivers.   It  is  only enabled for screens that have the
              "DPMS" option set (see the MONITOR section below).

       Option "Pixmap"  "bpp"
              This sets the pixmap format to use for depth 24.  Allowed values
              for  bpp  are  24 and 32.  Default: 32 unless driver constraints
              don't allow this (which is  rare).   Note:  some  clients  don't
              behave well when this value is set to 24.

       Option "PC98"  "boolean"
              Specify  that  the  machine  is  a Japanese PC-98 machine.  This
              should  not   be   enabled   for   anything   other   than   the
              Japanese-specific PC-98 architecture.  Default: auto-detected.

       Option "NoPM"  "boolean"
              Disables something to do with power management events.  Default:
              PM enabled on platforms that support it.

       Option "Xinerama"  "boolean"
              enable or disable XINERAMA extension.  Default is disabled.

       Option "AIGLX" "boolean"
              enable or disable AIGLX. AIGLX is enabled by default.

       Option "DRI2" "boolean"
              enable or disable DRI2. DRI2 is disabled by default.

       Option "GlxVisuals" "string"
              This option controls how many GLX visuals the GLX  modules  sets
              up.  The default value is typical, which will setup up a typical
              subset of  the  GLXFBConfigs  provided  by  the  driver  as  GLX
              visuals.   Other  options  are  minimal,  which  will set up the
              minimal set allowed by the GLX specification and all which  will
              setup GLX visuals for all GLXFBConfigs.

       Option "UseDefaultFontPath" "boolean"
              Include  the default font path even if other paths are specified
              in xorg.conf. If enabled, other font paths are included as well.
              Enabled by default.

       Option "IgnoreABI" "boolean"
              Allow  modules  built  for a different, potentially incompatible
              version of the X server to load. Disabled by default.

       Option "AllowEmptyInput" "boolean"
              If enabled, don't add the standard keyboard and  mouse  drivers,
              if  there  are  no input devices in the config file.  Enabled by
              default if  AutoAddDevices  and  AutoEnableDevices  is  enabled,
              otherwise disabled.  If AllowEmptyInput is on, devices using the
              kbd, mouse or vmmouse driver are ignored.

       Option "AutoAddDevices" "boolean"
              If this option is disabled, then no devices will be  added  from
              HAL events.  Enabled by default.

       Option "AutoEnableDevices" "boolean"
              If  this option is disabled, then the devices will be added (and
              the DevicePresenceNotify event  sent),  but  not  enabled,  thus
              leaving policy up to the client.  Enabled by default.

       Option "Log" "string"
              This option controls whether the log is flushed and/or synced to
              disk after each message.  Possible values  are  flush  or  sync.
              Unset by default.

MODULE SECTION

       The  Module section is used to specify which Xorg server modules should
       be loaded.  This section is ignored when the Xorg server  is  built  in
       static  form.   The type of modules normally loaded in this section are
       Xorg server extension modules.  Most  other  module  types  are  loaded
       automatically  when  they  are needed via other mechanisms.  The Module
       section is optional, as are all of the entries that may be specified in
       it.

       Entries  in  this  section  may  be  in  two forms.  The first and most
       commonly used form is an entry that uses the Load keyword, as described
       here:

       Load  "modulename"
              This  instructs the server to load the module called modulename.
              The module name given should be the module's standard name,  not
              the  module file name.  The standard name is case-sensitive, and
              does not include the "lib" prefix, or the ".a", ".o",  or  ".so"
              suffixes.

              Example:  the  DRI  extension  module  can  be  loaded  with the
              following entry:

                  Load "dri"

       Disable  "modulename"
              This  instructs  the  server  to  not  load  the  module  called
              modulename.   Some  modules are loaded by default in the server,
              and this overrides that default. If a Load instruction is  given
              for  the  same  module, it overrides the Disable instruction and
              the module is loaded.  The  module  name  given  should  be  the
              module's  standard  name,  not the module file name. As with the
              Load instruction, the standard name is case-sensitive, and  does
              not  include  the  "lib"  prefix,  or  the  ".a", ".o", or ".so"
              suffixes.

       The second form of entry is a  SubSection,  with  the  subsection  name
       being the module name, and the contents of the SubSection being Options
       that are passed to the module when it is loaded.

       Example: the extmod module (which contains  a  miscellaneous  group  of
       server  extensions)  can  be  loaded,  with  the  XFree86-DGA extension
       disabled by using the following entry:

           SubSection "extmod"
              Option  "omit XFree86-DGA"
           EndSubSection

       Modules are searched for in each directory specified in the  ModulePath
       search  path,  and  in  the  drivers,  extensions, input, internal, and
       multimedia subdirectories of each of those directories.  In addition to
       this,  operating  system  specific  subdirectories of all the above are
       searched first if they exist.

       To see what extension  modules  are  available,  check  the  extensions
       subdirectory under:

           /usr/lib/xorg/modules

       The  "extmod",  "dbe",  "dri",  "dri2",  "glx",  and "record" extension
       modules are loaded automatically, if they are present, unless  disabled
       with  "Disable"  entries.   It  is  recommended  that at very least the
       "extmod" extension module be loaded.  If it isn't, some  commonly  used
       server extensions (like the SHAPE extension) will not be available.

EXTENSIONS SECTION

       The Extensions section is used to specify which X11 protocol extensions
       should be enabled or disabled.  The Extensions section is optional,  as
       are all of the entries that may be specified in it.

       Entries  in  this section are listed as Option statements with the name
       of the extension as the first argument, and  a  boolean  value  as  the
       second.   The  extension  name  is case-sensitive, and matches the form
       shown in the output of "Xorg -extension ?".

              Example:  the  MIT-SHM  extension  can  be  disabled  with   the
              following entry:

                  Section "Extensions"
                      Option "MIT-SHM" "Disable"
                  EndSection

INPUTDEVICE SECTION

       The  config  file  may  have  multiple  InputDevice sections.  Recent X
       servers employ input hotplugging to add input  devices,  with  the  HAL
       backend  being  the  default  backend  for  X  servers since 1.4. It is
       usually not necessary to provide InputDevice sections in the  xorg.conf
       if hotplugging is enabled.

       If  hotplugging  is  disabled, there will normally be at least two: one
       for the core (primary) keyboard and  one  for  the  core  pointer.   If
       either of these two is missing, a default configuration for the missing
       ones will be used. In the absence of an explicitly specified core input
       device,  the  first InputDevice marked as CorePointer (or CoreKeyboard)
       is used.  If there is no match there, the first InputDevice  that  uses
       the  "mouse"  (or  "kbd") driver is used.  The final fallback is to use
       built-in default configurations.  Currently the  default  configuration
       may not work as expected on all platforms.

       InputDevice sections have the following format:

           Section "InputDevice"
               Identifier "name"
               Driver     "inputdriver"
               options
               ...
           EndSection

       The  Identifier  and  Driver  entries  are  required in all InputDevice
       sections.  All other entries are optional.

       The Identifier entry specifies the unique name for this  input  device.
       The Driver entry specifies the name of the driver to use for this input
       device.  When using  the  loadable  server,  the  input  driver  module
       "inputdriver"  will  be loaded for each active InputDevice section.  An
       InputDevice section is considered active if  it  is  referenced  by  an
       active  ServerLayout  section,  if it is referenced by the -keyboard or
       -pointer command line options, or if it is selected implicitly  as  the
       core  pointer  or  keyboard  device  in  the  absence  of such explicit
       references.  The most commonly used input drivers are evdev(4) on Linux
       systems, and kbd(4) and mousedrv(4) on other platforms.

       InputDevice  sections  recognise some driver-independent Options, which
       are described here.  See the individual input driver manual pages for a
       description of the device-specific options.

       Option "AutoServerLayout"  "boolean"
              Always  add  the device to the ServerLayout section used by this
              instance of the server. This affects implied layouts as well  as
              explicit  layouts  specified  in the configuration and/or on the
              command line.

       Option "CorePointer"
              Deprecated, use SendCoreEvents instead.

       Option "CoreKeyboard"
              Deprecated, use SendCoreEvents instead.

       Option "AlwaysCore"  "boolean"
              Deprecated, use SendCoreEvents instead.

       Option "SendCoreEvents"  "boolean"
              Both of these options are equivalent, and when enabled cause the
              input  device  to  report core events through the master device.
              They are enabled by default.  Any device configured to send core
              events  will be attached to the virtual core pointer or keyboard
              and control the cursor by default. Devices  with  SendCoreEvents
              disabled  will  be  "floating"  and  only  accessible by clients
              employing the  X  Input  extension.  This  option  controls  the
              startup  behavior  only,  a  device  may  be  reattached  or set
              floating at runtime.

       Option "SendDragEvents"  "boolean"
              Send core events while dragging. Enabled by default.

       For pointing devices, the following options control how the pointer  is
       accelerated or decelerated with respect to physical device motion. Most
       of these can be adjusted at runtime, see the  xinput(1)  man  page  for
       details.  Only  the  most  important acceleration options are discussed
       here.

       Option "AccelerationProfile"  "integer"
              Select the profile. In layman's terms, the  profile  constitutes
              the "feeling" of the acceleration. More formally, it defines how
              the transfer function (actual  acceleration  as  a  function  of
              current   device   velocity   and   acceleration   controls)  is
              constructed. This is mainly a matter of personal preference.

              0      classic (mostly compatible)
             -1      none (only constant deceleration is applied)
              1      device-dependent
              2      polynomial (polynomial function)
              3      smooth linear (soft knee, then linear)
              4      simple (normal when slow, otherwise accelerated)
              5      power (power function)
              6      linear (more speed, more acceleration)
              7      limited (like linear, but maxes out at threshold)

       Option "ConstantDeceleration"  "real"
              Makes the pointer go deceleration times slower than normal. Most
              useful for high-resolution devices.

       Option "AdaptiveDeceleration"  "real"
              Allows  to  actually  decelerate the pointer when going slow. At
              most, it will be adaptive  deceleration  times  slower.  Enables
              precise pointer placement without sacrificing speed.

       Option "AccelerationScheme"  "string"
              Selects the scheme, which is the underlying algorithm.

              predictable   default algorithm (behaving more predictable)
              lightweight   old acceleration code (as specified in the X protocol spec)
              none          no acceleration or deceleration

       Option "AccelerationNumerator"  "integer"

       Option "AccelerationDenominator"  "integer"
              Set  numerator  and  denominator of the acceleration factor. The
              acceleration  factor  is  a  rational   which,   together   with
              threshold,  can  be  used  to  tweak  profiles to suit the users
              needs. The simple and limited profiles  use  it  directly  (i.e.
              they  accelerate  by  the  factor), for other profiles it should
              hold that  a  higher  acceleration  factor  leads  to  a  faster
              pointer.  Typically,  1  is unaccelerated and values up to 5 are
              sensible.

       Option "AccelerationThreshold"  "integer"
              Set the threshold, which is roughly the velocity (usually device
              units  per 10 ms) required for acceleration to become effective.
              The precise effect varies with the profile however.

INPUTCLASS SECTION

       The config file may have multiple InputClass sections.  These  sections
       are optional and are used to provide configuration for a class of input
       devices as they are automatically added. An input device can match more
       than  one  InputClass  section. Each class can override settings from a
       previous class, so it is best to arrange the  sections  with  the  most
       generic matches first.

       InputClass sections have the following format:

           Section "InputClass"
               Identifier  "name"
               entries
               ...
               options
               ...
           EndSection

       The Identifier entry is required in all InputClass sections.  All other
       entries are optional.

       The Identifier entry specifies the unique name for  this  input  class.
       The Driver entry specifies the name of the driver to use for this input
       device.  After all classes have been examined, the "inputdriver" module
       from  the  first  Driver  entry will be enabled when using the loadable
       server.

       When an input device is automatically added,  its  characteristics  are
       checked  against  all  InputClass  sections.  Each  section can contain
       optional entries to narrow the match of  the  class.  If  none  of  the
       optional  entries  appear,  the  InputClass section is generic and will
       match any input device. If more than one of these entries appear,  they
       all must match for the configuration to apply.

       There  are  two types of match entries used in InputClass sections. The
       first allows various tokens to be matched  against  attributes  of  the
       device.  An entry can be constructed to match attributes from different
       devices by separating arguments with a '|' character. Multiple  entries
       of the same type may be supplied to add multiple matching conditions on
       the same attribute. For example:

           Section "InputClass"
               Identifier   "My Class"
               # product string must contain example and
               # either gizmo or gadget
               MatchProduct "example"
               MatchProduct "gizmo|gadget"
               ...
           EndSection

       MatchProduct  "matchproduct"
              This entry can be used to check if the substring  "matchproduct"
              occurs in the device's product name.

       MatchVendor  "matchvendor"
              This  entry  can be used to check if the substring "matchvendor"
              occurs in the device's vendor name.

       MatchDevicePath "matchdevice"
              This entry can be used to check if the device file  matches  the
              "matchdevice" pathname pattern.

       MatchOS "matchos"
              This  entry can be used to check if the operating system matches
              the  case-insensitive  "matchos"  string.  This  entry  is  only
              supported on platforms providing the uname(2) system call.

       MatchPnPID "matchpnp"
              The  device's  Plug and Play (PnP) ID can be checked against the
              "matchpnp" shell wildcard pattern.

       MatchUSBID "matchusb"
              The device's USB ID can be checked against the "matchusb"  shell
              wildcard pattern. The ID is constructed as lowercase hexadecimal
              numbers separated by a ':'. This  is  the  same  format  as  the
              lsusb(8) program.

       MatchDriver "matchdriver"
              Check   the  case-sensitive  string  "matchdriver"  against  the
              currently configured driver of the device. Ordering of  sections
              using this entry is important since it will not match unless the
              driver has  been  set  by  the  config  backend  or  a  previous
              InputClass section.

       MatchTag "matchtag"
              This  entry  can be used to check if tags assigned by the config
              backend matches the "matchtag" pattern. A match is found  if  at
              least  one  of the tags given in "matchtag" matches at least one
              of the tags assigned by the backend.

       The second type of entry is used to match device types.  These  entries
       take a boolean argument similar to Option entries.

       MatchIsKeyboard     "bool"

       MatchIsPointer      "bool"

       MatchIsJoystick     "bool"

       MatchIsTablet       "bool"

       MatchIsTouchpad     "bool"

       MatchIsTouchscreen  "bool"

       When  an  input  device has been matched to the InputClass section, any
       Option entries are applied  to  the  device.  One  InputClass  specific
       Option   is  recognized.  See  the  InputDevice  section  above  for  a
       description of the remaining Option entries.

       Option "Ignore" "boolean"
              This optional entry specifies that the device should be  ignored
              entirely,  and  not added to the server. This can be useful when
              the device is handled by another program and no X events  should
              be generated.

DEVICE SECTION

       The  config  file  may have multiple Device sections.  There must be at
       least one, for the video card being used.

       Device sections have the following format:

           Section "Device"
               Identifier "name"
               Driver     "driver"
               entries
               ...
           EndSection

       The Identifier and Driver entries are required in all Device  sections.
       All other entries are optional.

       The  Identifier  entry  specifies  the  unique  name  for this graphics
       device.  The Driver entry specifies the name of the driver to  use  for
       this  graphics  device.   When  using  the  loadable server, the driver
       module "driver" will be loaded  for  each  active  Device  section.   A
       Device  section  is  considered active if it is referenced by an active
       Screen section.

       Device sections recognise some driver-independent entries and  Options,
       which   are  described  here.   Not  all  drivers  make  use  of  these
       driver-independent entries, and many of those  that  do  don't  require
       them to be specified because the information is auto-detected.  See the
       individual graphics driver manual pages for further  information  about
       this,  and for a description of the device-specific options.  Note that
       most of the Options listed here (but not  the  other  entries)  may  be
       specified  in the Screen section instead of here in the Device section.

       BusID  "bus-id"
              This specifies the bus  location  of  the  graphics  card.   For
              PCI/AGP    cards,    the    bus-id    string    has   the   form
              PCI:bus:device:function (e.g., "PCI:1:0:0" might be  appropriate
              for an AGP card).  This field is usually optional in single-head
              configurations when using the primary graphics card.  In  multi-
              head  configurations, or when using a secondary graphics card in
              a single-head configuration, this entry is mandatory.  Its  main
              purpose  is to make an unambiguous connection between the device
              section and the hardware it is representing.   This  information
              can usually be found by running the pciaccess tool scanpci.

       Screen  number
              This option is mandatory for cards where a single PCI entity can
              drive more than one display  (i.e.,  multiple  CRTCs  sharing  a
              single  graphics  accelerator  and  video  memory).   One Device
              section is required for each head, and this parameter determines
              which  head  each  of the Device sections applies to.  The legal
              values of number range from 0 to one less than the total  number
              of  heads  per  entity.   Most  drivers require that the primary
              screen (0) be present.

       Chipset  "chipset"
              This usually optional entry specifies the chipset  used  on  the
              graphics  board.   In  most  cases  this  entry  is not required
              because the drivers will probe the  hardware  to  determine  the
              chipset  type.   Don't  specify  it  unless  the driver-specific
              documentation recommends that you do.

       Ramdac  "ramdac-type"
              This optional entry specifies the type of  RAMDAC  used  on  the
              graphics  board.  This is only used by a few of the drivers, and
              in most cases it is not required because the drivers will  probe
              the hardware to determine the RAMDAC type where possible.  Don't
              specify it unless the driver-specific  documentation  recommends
              that you do.

       DacSpeed  speed

       DacSpeed  speed-8 speed-16 speed-24 speed-32
              This  optional entry specifies the RAMDAC speed rating (which is
              usually printed on the RAMDAC chip).  The speed is in MHz.  When
              one  value  is given, it applies to all framebuffer pixel sizes.
              When multiple values are given, they apply  to  the  framebuffer
              pixel  sizes 8, 16, 24 and 32 respectively.  This is not used by
              many drivers, and only needs to  be  specified  when  the  speed
              rating  of the RAMDAC is different from the defaults built in to
              driver,  or  when  the  driver  can't  auto-detect  the  correct
              defaults.    Don't   specify   it   unless  the  driver-specific
              documentation recommends that you do.

       Clocks  clock ...
              specifies the pixel that are on your graphics board.  The clocks
              are  in  MHz,  and  may be specified as a floating point number.
              The value is stored internally to the nearest kHz.  The ordering
              of  the  clocks  is important.  It must match the order in which
              they are selected on the graphics board.  Multiple Clocks  lines
              may  be  specified,  and  each is concatenated to form the list.
              Most drivers do not use this entry, and it is only required  for
              some  older  boards with non-programmable clocks.  Don't specify
              this entry unless the driver-specific  documentation  explicitly
              recommends that you do.

       ClockChip  "clockchip-type"
              This  optional  entry  is used to specify the clock chip type on
              graphics boards which have a programmable clock generator.  Only
              a  few  Xorg  drivers  support  programmable  clock  chips.  For
              details, see the appropriate driver manual page.

       VideoRam  mem
              This optional entry specifies the amount of video  ram  that  is
              installed  on  the  graphics board.  This is measured in kBytes.
              In most cases this is  not  required  because  the  Xorg  server
              probes  the  graphics  board  to  determine  this quantity.  The
              driver-specific documentation should indicate when it  might  be
              needed.

       BiosBase  baseaddress
              This optional entry specifies the base address of the video BIOS
              for the VGA board.  This address is normally auto-detected,  and
              should  only  be  specified if the driver-specific documentation
              recommends it.

       MemBase  baseaddress
              This optional entry specifies  the  memory  base  address  of  a
              graphics board's linear frame buffer.  This entry is not used by
              many drivers, and it should only be  specified  if  the  driver-
              specific documentation recommends it.

       IOBase  baseaddress
              This  optional  entry specifies the IO base address.  This entry
              is not used by many drivers, and it should only be specified  if
              the driver-specific documentation recommends it.

       ChipID  id
              This  optional  entry  specifies a numerical ID representing the
              chip type.  For PCI cards, it is usually the  device  ID.   This
              can be used to override the auto-detection, but that should only
              be done when the driver-specific documentation recommends it.

       ChipRev  rev
              This optional entry specifies the chip  revision  number.   This
              can be used to override the auto-detection, but that should only
              be done when the driver-specific documentation recommends it.

       TextClockFreq  freq
              This optional entry specifies the pixel clock frequency that  is
              used  for  the regular text mode.  The frequency is specified in
              MHz.  This is rarely used.

       Option "ModeDebug" "boolean"
              Enable  printing  of  additional  debugging  information   about
              modesetting to the server log.

       Options
              Option  flags  may  be  specified in the Device sections.  These
              include driver-specific options and driver-independent  options.
              The  former  are described in the driver-specific documentation.
              Some of the latter are described below in the section about  the
              Screen section, and they may also be included here.

VIDEOADAPTOR SECTION

       Nobody wants to say how this works.  Maybe nobody knows ...

MONITOR SECTION

       The  config  file  may  have  multiple  Monitor sections.  There should
       normally be at least one, for the monitor being  used,  but  a  default
       configuration will be created when one isn't specified.

       Monitor sections have the following format:

           Section "Monitor"
               Identifier "name"
               entries
               ...
           EndSection

       The  only mandatory entry in a Monitor section is the Identifier entry.

       The Identifier entry specifies the unique name for this  monitor.   The
       Monitor   section   may  be  used  to  provide  information  about  the
       specifications  of   the   monitor,   monitor-specific   Options,   and
       information about the video modes to use with the monitor.

       With  RandR  1.2-enabled  drivers,  monitor  sections  may  be  tied to
       specific outputs of the video card.   Using  the  name  of  the  output
       defined  by  the video driver plus the identifier of a monitor section,
       one associates a monitor section with an output by adding an option  to
       the Device section in the following format:

       Option "Monitor-outputname" "monitorsection"

       (for example, Option "Monitor-VGA" "VGA monitor" for a VGA output)

       In  the absence of specific association of monitor sections to outputs,
       if a monitor section is present the server will associate  it  with  an
       output    to    preserve   compatibility   for   previous   single-head
       configurations.

       Specifying video modes is optional because the server will use the  DDC
       or other information provided by the monitor to automatically configure
       the list of modes available.  When modes are  specified  explicitly  in
       the  Monitor  section (with the Modes, ModeLine, or UseModes keywords),
       built-in modes with the same names are not  included.   Built-in  modes
       with different names are, however, still implicitly included, when they
       meet the requirements of the monitor.

       The entries that may be used in Monitor sections are described below.

       VendorName  "vendor"
              This optional entry specifies the monitor's manufacturer.

       ModelName  "model"
              This optional entry specifies the monitor's model.

       HorizSync  horizsync-range
              gives the range(s) of horizontal sync frequencies  supported  by
              the  monitor.   horizsync-range may be a comma separated list of
              either discrete values or ranges of values.  A range  of  values
              is two values separated by a dash.  By default the values are in
              units of kHz.  They may be specified in MHz or Hz if MHz  or  Hz
              is added to the end of the line.  The data given here is used by
              the Xorg server to determine  if  video  modes  are  within  the
              specifications  of  the  monitor.   This  information  should be
              available in the monitor's handbook.  If this entry is  omitted,
              a default range of 28-33kHz is used.

       VertRefresh  vertrefresh-range
              gives  the range(s) of vertical refresh frequencies supported by
              the monitor.  vertrefresh-range may be a comma separated list of
              either  discrete  values or ranges of values.  A range of values
              is two values separated by a dash.  By default the values are in
              units  of Hz.  They may be specified in MHz or kHz if MHz or kHz
              is added to the end of the line.  The data given here is used by
              the  Xorg  server  to  determine  if  video modes are within the
              specifications of  the  monitor.   This  information  should  be
              available  in the monitor's handbook.  If this entry is omitted,
              a default range of 43-72Hz is used.

       DisplaySize  width height
              This optional entry gives the width and height, in  millimetres,
              of  the  picture  area of the monitor.  If given this is used to
              calculate the horizontal and vertical pitch (DPI) of the screen.

       Gamma  gamma-value

       Gamma  red-gamma green-gamma blue-gamma
              This  is an optional entry that can be used to specify the gamma
              correction for the monitor.  It may be  specified  as  either  a
              single value or as three separate RGB values.  The values should
              be in the range 0.1 to 10.0, and the default is  1.0.   Not  all
              drivers are capable of using this information.

       UseModes  "modesection-id"
              Include  the  set  of  modes  listed in the Modes section called
              modesection-id.  This makes all of the  modes  defined  in  that
              section available for use by this monitor.

       Mode  "name"
              This is an optional multi-line entry that can be used to provide
              definitions for video modes for the monitor.  In most cases this
              isn't  necessary because the built-in set of VESA standard modes
              will be sufficient.  The Mode keyword indicates the start  of  a
              multi-line  video  mode  description.   The  mode description is
              terminated with  the  EndMode  keyword.   The  mode  description
              consists of the following entries:

              DotClock  clock
                  is the dot (pixel) clock rate to be used for the mode.

              HTimings  hdisp hsyncstart hsyncend htotal
                  specifies the horizontal timings for the mode.

              VTimings  vdisp vsyncstart vsyncend vtotal
                  specifies the vertical timings for the mode.

              Flags  "flag" ...
                  specifies  an optional set of mode flags, each of which is a
                  separate string in  double  quotes.   "Interlace"  indicates
                  that  the mode is interlaced.  "DoubleScan" indicates a mode
                  where each scanline is doubled.  "+HSync" and  "-HSync"  can
                  be  used  to  select  the  polarity  of  the  HSync  signal.
                  "+VSync" and "-VSync" can be used to select the polarity  of
                  the  VSync  signal.   "Composite"  can  be  used  to specify
                  composite  sync  on  hardware  where  this   is   supported.
                  Additionally, on some hardware, "+CSync" and "-CSync" may be
                  used to select the composite sync polarity.

              HSkew  hskew
                  specifies the number of pixels (towards the  right  edge  of
                  the  screen)  by  which  the  display enable signal is to be
                  skewed.  Not all drivers use this information.  This  option
                  might   become  necessary  to  override  the  default  value
                  supplied by the server (if any).  "Roving" horizontal  lines
                  indicate  this value needs to be increased.  If the last few
                  pixels on a scan line appear on the left of the screen, this
                  value should be decreased.

              VScan  vscan
                  specifies  the  number  of times each scanline is painted on
                  the screen.  Not all drivers use this  information.   Values
                  less  than  1  are  treated  as  1,  which  is  the default.
                  Generally, the "DoubleScan"  Flag  mentioned  above  doubles
                  this value.

       ModeLine  "name" mode-description
              This  entry  is a more compact version of the Mode entry, and it
              also can be used to specify video modes for the monitor.   is  a
              single  line  format  for specifying video modes.  In most cases
              this isn't necessary because the built-in set of  VESA  standard
              modes will be sufficient.

              The  mode-description  is  in  four sections, the first three of
              which are mandatory.  The first is the dot (pixel) clock.   This
              is  a single number specifying the pixel clock rate for the mode
              in MHz.  The second section is a list of four numbers specifying
              the   horizontal   timings.    These   numbers  are  the  hdisp,
              hsyncstart, hsyncend, and htotal values.  The third section is a
              list  of  four  numbers  specifying the vertical timings.  These
              numbers are the vdisp, vsyncstart, vsyncend, and vtotal  values.
              The   final   section  is  a  list  of  flags  specifying  other
              characteristics of the mode.  Interlace indicates that the  mode
              is  interlaced.  DoubleScan indicates a mode where each scanline
              is doubled.  +HSync  and  -HSync  can  be  used  to  select  the
              polarity  of the HSync signal.  +VSync and -VSync can be used to
              select the polarity of the VSync signal.  Composite can be  used
              to  specify  composite sync on hardware where this is supported.
              Additionally, on some hardware, +CSync and -CSync may be used to
              select the composite sync polarity.  The HSkew and VScan options
              mentioned above in the Modes entry description can also be  used
              here.

       Option "DPMS"  "bool"
              This  option  controls whether the server should enable the DPMS
              extension for power management for this screen.  The default  is
              to enable the extension.

       Option "SyncOnGreen"  "bool"
              This  option  controls  whether  the video card should drive the
              sync signal on the green color pin.  Not all cards support  this
              option,  and  most  monitors  do not require it.  The default is
              off.

       Option "Primary"  "bool"
              This optional entry specifies that the monitor should be treated
              as the primary monitor. (RandR 1.2-supporting drivers only)

       Option "PreferredMode"  "string"
              This  optional  entry  specifies  a  mode  to  be  marked as the
              preferred initial mode of the  monitor.   (RandR  1.2-supporting
              drivers only)

       Option "Position"  "x y"
              This optional entry specifies the position of the monitor within
              the X screen.  (RandR 1.2-supporting drivers only)

       Option "LeftOf"  "output"
              This  optional  entry  specifies  that  the  monitor  should  be
              positioned  to the left of the output (not monitor) of the given
              name.  (RandR 1.2-supporting drivers only)

       Option "RightOf"  "output"
              This  optional  entry  specifies  that  the  monitor  should  be
              positioned to the right of the output (not monitor) of the given
              name.  (RandR 1.2-supporting drivers only)

       Option "Above"  "output"
              This  optional  entry  specifies  that  the  monitor  should  be
              positioned  above  the  output  (not monitor) of the given name.
              (RandR 1.2-supporting drivers only)

       Option "Below"  "output"
              This  optional  entry  specifies  that  the  monitor  should  be
              positioned  below  the  output  (not monitor) of the given name.
              (RandR 1.2-supporting drivers only)

       Option "Enable"  "bool"
              This optional entry specifies  whether  the  monitor  should  be
              turned  on  at  startup.  By default, the server will attempt to
              enable all connected monitors.   (RandR  1.2-supporting  drivers
              only)

       Option "DefaultModes"  "bool"
              This  optional  entry  specifies  whether  the server should add
              supported default modes to the list of  modes  offered  on  this
              monitor.  By  default,  the  server  will add default modes; you
              should only disable this if you can guarantee that EDID will  be
              available  at  all  times, or if you have added custom modelines
              which the server can use.  (RandR 1.2-supporting drivers only)

       Option "MinClock"  "frequency"
              This optional entry specifies the minimum  dot  clock,  in  kHz,
              that is supported by the monitor.

       Option "MaxClock"  "frequency"
              This  optional  entry  specifies  the maximum dot clock, in kHz,
              that is supported by the monitor.

       Option "Ignore"  "bool"
              This optional entry specifies that the monitor should be ignored
              entirely, and not reported through RandR.  This is useful if the
              hardware reports the  presence  of  outputs  that  don't  exist.
              (RandR 1.2-supporting drivers only)

       Option "Rotate"  "rotation"
              This  optional entry specifies the initial rotation of the given
              monitor.   Valid  values  for  rotation  are  "normal",  "left",
              "right", and "inverted".  (RandR 1.2-supporting drivers only)

MODES SECTION

       The  config  file  may  have  multiple  Modes sections, or none.  These
       sections provide a way of defining sets of video modes independently of
       the  Monitor  sections.   Monitor  sections may include the definitions
       provided in these sections by using  the  UseModes  keyword.   In  most
       cases  the Modes sections are not necessary because the built-in set of
       VESA standard modes will be sufficient.

       Modes sections have the following format:

           Section "Modes"
               Identifier "name"
               entries
               ...
           EndSection

       The Identifier entry specifies the unique name for  this  set  of  mode
       descriptions.   The  other  entries permitted in Modes sections are the
       Mode and ModeLine entries that  are  described  above  in  the  Monitor
       section.

SCREEN SECTION

       The  config  file  may have multiple Screen sections.  There must be at
       least one, for the "screen" being  used.   A  "screen"  represents  the
       binding  of  a  graphics device (Device section) and a monitor (Monitor
       section).  A Screen section is considered "active" if it is  referenced
       by  an  active  ServerLayout  section  or  by  the -screen command line
       option.  If neither of those is present, the first Screen section found
       in the config file is considered the active one.

       Screen sections have the following format:

           Section "Screen"
               Identifier "name"
               Device     "devid"
               Monitor    "monid"
               entries
               ...
               SubSection "Display"
                  entries
                  ...
               EndSubSection
               ...
           EndSection

       The Identifier entry is mandatory.  All others are optional.

       The  Identifier  entry  specifies the unique name for this screen.  The
       Screen section provides  information  specific  to  the  whole  screen,
       including screen-specific Options.  In multi-head configurations, there
       will be multiple active  Screen  sections,  one  for  each  head.   The
       entries available for this section are:

       Device  "device-id"
              This mandatory entry specifies the Device section to be used for
              this screen.  This is what ties a specific graphics  card  to  a
              screen.   The  device-id  must  match the Identifier of a Device
              section in the config file.

       Monitor  "monitor-id"
              specifies which monitor description  is  to  be  used  for  this
              screen.    If  a  Monitor  name  is  not  specified,  a  default
              configuration is used.  Currently the default configuration  may
              not function as expected on all platforms.

       VideoAdaptor  "xv-id"
              specifies  an  optional  Xv video adaptor description to be used
              with this screen.

       DefaultDepth  depth
              specifies which color depth the server should  use  by  default.
              The -depth command line option can be used to override this.  If
              neither is specified, the default depth is driver-specific,  but
              in most cases is 8.

       DefaultFbBpp  bpp
              specifies  which  framebuffer  layout  to  use  by default.  The
              -fbbpp command line option can be used  to  override  this.   In
              most  cases  the  driver  will  chose the best default value for
              this.  The only case where there is even a choice in this  value
              is  for  depth 24, where some hardware supports both a packed 24
              bit framebuffer layout and a sparse 32 bit framebuffer layout.

       Options
              Various Option flags may be specified  in  the  Screen  section.
              Some  are  driver-specific  and  are  described  in  the  driver
              documentation.   Others   are   driver-independent,   and   will
              eventually be described here.

       Option "Accel"
              Enables  XAA  (X  Acceleration  Architecture),  a mechanism that
              makes video cards' 2D hardware  acceleration  available  to  the
              Xorg  server.   This  option  is  on  by  default, but it may be
              necessary to turn it off if there are bugs in the driver.  There
              are  many  options  to  disable specific accelerated operations,
              listed below.  Note that disabling an  operation  will  have  no
              effect  if the operation is not accelerated (whether due to lack
              of support in the hardware or in the driver).

       Option "InitPrimary" "boolean"
              Use the Int10 module to initialize the  primary  graphics  card.
              Normally,  only  secondary cards are soft-booted using the Int10
              module, as the primary card has already been initialized by  the
              BIOS at boot time.  Default: false.

       Option "NoInt10" "boolean"
              Disables  the Int10 module, a module that uses the int10 call to
              the BIOS of the graphics card to initialize it.  Default: false.

       Option "NoMTRR"
              Disables MTRR (Memory Type Range Register) support, a feature of
              modern processors which  can  improve  video  performance  by  a
              factor  of up to 2.5.  Some hardware has buggy MTRR support, and
              some video drivers have been  known  to  exhibit  problems  when
              MTRR's are used.

       Option "XaaNoCPUToScreenColorExpandFill"
              Disables  accelerated  rectangular  expansion  blits from source
              patterns  stored  in  system  memory  (using   a   memory-mapped
              aperture).

       Option "XaaNoColor8x8PatternFillRect"
              Disables  accelerated  fills  of  a  rectangular  region  with a
              full-color pattern.

       Option "XaaNoColor8x8PatternFillTrap"
              Disables accelerated  fills  of  a  trapezoidal  region  with  a
              full-color pattern.

       Option "XaaNoDashedBresenhamLine"
              Disables accelerated dashed Bresenham line draws.

       Option "XaaNoDashedTwoPointLine"
              Disables  accelerated  dashed  line  draws between two arbitrary
              points.

       Option "XaaNoImageWriteRect"
              Disables  accelerated  transfers   of   full-color   rectangular
              patterns   from   system   memory   to  video  memory  (using  a
              memory-mapped aperture).

       Option "XaaNoMono8x8PatternFillRect"
              Disables accelerated  fills  of  a  rectangular  region  with  a
              monochrome pattern.

       Option "XaaNoMono8x8PatternFillTrap"
              Disables  accelerated  fills  of  a  trapezoidal  region  with a
              monochrome pattern.

       Option "XaaNoOffscreenPixmaps"
              Disables accelerated draws  into  pixmaps  stored  in  offscreen
              video memory.

       Option "XaaNoPixmapCache"
              Disables caching of patterns in offscreen video memory.

       Option "XaaNoScanlineCPUToScreenColorExpandFill"
              Disables  accelerated  rectangular  expansion  blits from source
              patterns stored in system memory (one scan line at a time).

       Option "XaaNoScanlineImageWriteRect"
              Disables  accelerated  transfers   of   full-color   rectangular
              patterns  from system memory to video memory (one scan line at a
              time).

       Option "XaaNoScreenToScreenColorExpandFill"
              Disables accelerated rectangular  expansion  blits  from  source
              patterns stored in offscreen video memory.

       Option "XaaNoScreenToScreenCopy"
              Disables accelerated copies of rectangular regions from one part
              of video memory to another part of video memory.

       Option "XaaNoSolidBresenhamLine"
              Disables accelerated solid Bresenham line draws.

       Option "XaaNoSolidFillRect"
              Disables accelerated solid-color fills of rectangles.

       Option "XaaNoSolidFillTrap"
              Disables accelerated solid-color fills of Bresenham  trapezoids.

       Option "XaaNoSolidHorVertLine"
              Disables accelerated solid horizontal and vertical line draws.

       Option "XaaNoSolidTwoPointLine"
              Disables  accelerated  solid  line  draws  between two arbitrary
              points.

       Each  Screen  section  may  optionally  contain  one  or  more  Display
       subsections.     Those   subsections   provide   depth/fbbpp   specific
       configuration information, and the one  chosen  depends  on  the  depth
       and/or fbbpp that is being used for the screen.  The Display subsection
       format is described in the section below.

DISPLAY SUBSECTION

       Each  Screen  section  may  have  multiple  Display  subsections.   The
       "active"  Display subsection is the first that matches the depth and/or
       fbbpp values being used, or failing that, the first that has neither  a
       depth  or fbbpp value specified.  The Display subsections are optional.
       When there isn't one that matches the depth and/or fbbpp  values  being
       used,  all the parameters that can be specified here fall back to their
       defaults.

       Display subsections have the following format:

               SubSection "Display"
                   Depth  depth
                   entries
                   ...
               EndSubSection

       Depth  depth
              This entry specifies what colour depth the Display subsection is
              to  be used for.  This entry is usually specified, but it may be
              omitted to create a match-all Display subsection or when wishing
              to  match  only against the FbBpp parameter.  The range of depth
              values that are allowed depends on  the  driver.   Most  drivers
              support  8,  15,  16  and 24.  Some also support 1 and/or 4, and
              some may support other values (like 30).  Note: depth means  the
              number  of  bits  in a pixel that are actually used to determine
              the pixel colour.  32 is not a valid depth value.  Most hardware
              that  uses  32  bits  per pixel only uses 24 of them to hold the
              colour information, which means that the colour depth is 24, not
              32.

       FbBpp  bpp
              This   entry  specifies  the  framebuffer  format  this  Display
              subsection is to be used for.  This entry is  only  needed  when
              providing  depth 24 configurations that allow a choice between a
              24 bpp packed framebuffer format and a 32bpp sparse  framebuffer
              format.  In most cases this entry should not be used.

       Weight  red-weight green-weight blue-weight
              This  optional  entry specifies the relative RGB weighting to be
              used for a screen is being used at depth  16  for  drivers  that
              allow  multiple  formats.   This  may also be specified from the
              command line with the -weight option (see Xorg(1)).

       Virtual  xdim ydim
              This optional entry specifies the virtual screen  resolution  to
              be  used.   xdim  must  be a multiple of either 8 or 16 for most
              drivers, and a multiple of 32 when running in  monochrome  mode.
              The  given  value  will be rounded down if this is not the case.
              Video modes which are too large for the specified  virtual  size
              will  be  rejected.   If  this entry is not present, the virtual
              screen resolution will be set to accommodate all the valid video
              modes   given   in   the  Modes  entry.   Some  drivers/hardware
              combinations do not  support  virtual  screens.   Refer  to  the
              appropriate driver-specific documentation for details.

       ViewPort  x0 y0
              This  optional  entry  sets the upper left corner of the initial
              display.   This  is  only  relevant  when  the  virtual   screen
              resolution is different from the resolution of the initial video
              mode.  If this entry is not given, then the initial display will
              be centered in the virtual display area.

       Modes  "mode-name" ...
              This  optional  entry  specifies the list of video modes to use.
              Each mode-name specified must be in double  quotes.   They  must
              correspond  to  those specified or referenced in the appropriate
              Monitor section (including implicitly referenced  built-in  VESA
              standard  modes).   The  server will delete modes from this list
              which don't satisfy various requirements.  The first valid  mode
              in  this list will be the default display mode for startup.  The
              list of valid modes is  converted  internally  into  a  circular
              list.    It  is  possible  to  switch  to  the  next  mode  with
              Ctrl+Alt+Keypad-Plus   and   to   the   previous    mode    with
              Ctrl+Alt+Keypad-Minus.   When  this  entry is omitted, the valid
              modes referenced by the  appropriate  Monitor  section  will  be
              used.   If  the  Monitor  section  contains  no  modes, then the
              selection will be taken from the built-in VESA standard modes.

       Visual  "visual-name"
              This optional entry sets the default root visual type.  This may
              also  be specified from the command line (see the Xserver(1) man
              page).  The visual types available for depth 8 are  (default  is
              PseudoColor):

                  StaticGray
                  GrayScale
                  StaticColor
                  PseudoColor
                  TrueColor
                  DirectColor

              The  visual  type  available  for  the  depths 15, 16 and 24 are
              (default is TrueColor):

                  TrueColor
                  DirectColor

              Not all drivers support DirectColor at these depths.

              The visual types available for  the  depth  4  are  (default  is
              StaticColor):

                  StaticGray
                  GrayScale
                  StaticColor
                  PseudoColor

              The  visual  type  available  for  the  depth  1 (monochrome) is
              StaticGray.

       Black  red green blue
              This optional entry allows the "black" colour to  be  specified.
              This is only supported at depth 1.  The default is black.

       White  red green blue
              This  optional  entry allows the "white" colour to be specified.
              This is only supported at depth 1.  The default is white.

       Options
              Option flags may be specified in the Display subsections.  These
              may   include  driver-specific  options  and  driver-independent
              options.   The  former  are  described  in  the  driver-specific
              documentation.   Some  of  the latter are described above in the
              section about the Screen section, and they may also be  included
              here.

SERVERLAYOUT SECTION

       The  config  file  may  have multiple ServerLayout sections.  A "server
       layout" represents the binding of one or more screens (Screen sections)
       and one or more input devices (InputDevice sections) to form a complete
       configuration.  In multi-head configurations,  it  also  specifies  the
       relative  layout  of  the  heads.  A ServerLayout section is considered
       "active" if it is referenced by the -layout command line option  or  by
       an  Option  "DefaultServerLayout" entry in the ServerFlags section (the
       former takes precedence over the latter).  If  those  options  are  not
       used,  the  first  ServerLayout  section  found  in  the config file is
       considered the active one.  If no ServerLayout  sections  are  present,
       the  single  active  screen  and  two  active  (core) input devices are
       selected as described in the relevant sections above.

       ServerLayout sections have the following format:

           Section "ServerLayout"
               Identifier   "name"
               Screen       "screen-id"
               ...
               InputDevice  "idev-id"
               ...
               options
               ...
           EndSection

       Each ServerLayout section must have an Identifier entry  and  at  least
       one Screen entry.

       The  Identifier entry specifies the unique name for this server layout.
       The ServerLayout section provides information  specific  to  the  whole
       session,  including  session-specific Options.  The ServerFlags options
       (described above) may be specified here, and ones given  here  override
       those given in the ServerFlags section.

       The entries that may be used in this section are described here.

       Screen  screen-num "screen-id" position-information
              One of these entries must be given for each screen being used in
              a session.  The screen-id field is mandatory, and specifies  the
              Screen  section  being  referenced.   The  screen-num  field  is
              optional, and may be  used  to  specify  the  screen  number  in
              multi-head  configurations.   When  this  field  is omitted, the
              screens will be numbered in the order that they are  listed  in.
              The  numbering  starts  from  0,  and  must be consecutive.  The
              position-information field describes the  way  multiple  screens
              are  positioned.  There are a number of different ways that this
              information can be provided:

              x y

              Absolute  x y
                  These both specify that the upper left corner's  coordinates
                  are  (x,y).   The  Absolute keyword is optional.  Some older
                  versions of XFree86 (4.2 and earlier)  don't  recognise  the
                  Absolute  keyword,  so  it's  safest  to  just  specify  the
                  coordinates without it.

              RightOf   "screen-id"

              LeftOf    "screen-id"

              Above     "screen-id"

              Below     "screen-id"

              Relative  "screen-id" x y
                  These give the screen's location relative to another screen.
                  The first four position the screen immediately to the right,
                  left, above or below the other screen.  When positioning  to
                  the  right  or  left,  the  top  edges  are  aligned.   When
                  positioning above or below, the left edges are aligned.  The
                  Relative  form  specifies  the offset of the screen's origin
                  (upper left  corner)  relative  to  the  origin  of  another
                  screen.

       InputDevice  "idev-id" "option" ...
              One of these entries should be given for each input device being
              used in a session.  Normally at least two are required, one each
              for  the  core pointer and keyboard devices.  If either of those
              is missing, suitable InputDevice entries are searched for  using
              the  method  described  above  in  the INPUTDEVICE section.  The
              idev-id field is  mandatory,  and  specifies  the  name  of  the
              InputDevice  section  being  referenced.  Multiple option fields
              may be specified, each in double quotes.  The options  permitted
              here are any that may also be given in the InputDevice sections.
              Normally only session-specific input  device  options  would  be
              used here.  The most commonly used options are:

                  "CorePointer"
                  "CoreKeyboard"
                  "SendCoreEvents"

              and  the  first two should normally be used to indicate the core
              pointer and core keyboard devices respectively.

       Options
              In addition to  the  following,  any  option  permitted  in  the
              ServerFlags  section  may also be specified here.  When the same
              option appears in both places, the value  given  here  overrides
              the one given in the ServerFlags section.

       Option "IsolateDevice"  "bus-id"
              Restrict  device  resets to the specified bus-id.  See the BusID
              option (described in DEVICE SECTION, above) for  the  format  of
              the  bus-id  parameter.   This  option  overrides SingleCard, if
              specified.  At present, only PCI devices can be isolated in this
              manner.

       Option "SingleCard"  "boolean"
              As  IsolateDevice, except that the bus ID of the first device in
              the layout is used.

       Here is an  example  of  a  ServerLayout  section  for  a  dual  headed
       configuration with two mice:

           Section "ServerLayout"
               Identifier  "Layout 1"
               Screen      "MGA 1"
               Screen      "MGA 2" RightOf "MGA 1"
               InputDevice "Keyboard 1" "CoreKeyboard"
               InputDevice "Mouse 1"    "CorePointer"
               InputDevice "Mouse 2"    "SendCoreEvents"
               Option      "BlankTime"  "5"
           EndSection

DRI SECTION

       This  optional  section  is  used  to  provide some information for the
       Direct Rendering Infrastructure.  Details  about  the  format  of  this
       section can be found on-line at <http://dri.freedesktop.org/>.

VENDOR SECTION

       The  optional  Vendor  section  may  be used to provide vendor-specific
       configuration information.  Multiple Vendor sections  may  be  present,
       and  they  may  contain  an Identifier entry and multiple Option flags.
       The data therein is not used in this release.

SEE ALSO

       General: X(7), Xserver(1), Xorg(1), cvt(1), gtf(1).

       Not all modules or interfaces are available on all platforms.

       Display  drivers:  apm(4),  ati(4),  chips(4),   cirrus(4),   cyrix(4),
       fbdev(4),  glide(4),  glint(4),  i128(4),  i740(4), imstt(4), intel(4),
       mga(4),  neomagic(4),   nv(4),   openchrome(4),   r128(4),   radeon(4),
       rendition(4),    savage(4),   s3virge(4),   siliconmotion(4),   sis(4),
       sisusb(4),  sunbw2(4),  suncg14(4),  suncg3(4),  suncg6(4),  sunffb(4),
       sunleo(4),   suntcx(4),   tdfx(4),   trident(4),   tseng(4),   vesa(4),
       vmware(4), voodoo(4), wsfb(4), xgi(4), xgixp(4).

       Input drivers: acecad(4), citron(4), elographics(4), evdev(4), fpit(4),
       joystick(4),     kbd(4),    mousedrv(4),    mutouch(4),    penmount(4),
       synaptics(4), vmmouse(4), void(4), wacom(4).

       Other modules and interfaces: exa(4), fbdevhw(4), v4l(4).

AUTHORS

       This   manual   page   was   largely   rewritten   by    David    Dawes
       <dawes@xfree86.org>.