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       dmidecode - DMI table decoder


       dmidecode [OPTIONS]


       dmidecode  is  a  tool  for  dumping a computer’s DMI (some say SMBIOS)
       table contents in  a  human-readable  format.  This  table  contains  a
       description  of  the  system’s  hardware  components,  as well as other
       useful pieces of information such as serial numbers and BIOS  revision.
       Thanks  to this table, you can retrieve this information without having
       to probe for the actual hardware.  While this is a good point in  terms
       of report speed and safeness, this also makes the presented information
       possibly unreliable.

       The DMI table doesn’t only describe what the system is  currently  made
       of,  it  also  can  report the possible evolutions (such as the fastest
       supported CPU or the maximal amount of memory supported).

       SMBIOS stands for System Management BIOS, while DMI stands for  Desktop
       Management  Interface. Both standards are tightly related and developed
       by the DMTF (Desktop Management Task Force).

       As you run it, dmidecode will try  to  locate  the  DMI  table.  If  it
       succeeds,  it  will then parse this table and display a list of records
       like this one:

       Handle 0x0002, DMI type 2, 8 bytes.  Base Board Information
               Manufacturer: Intel
               Product Name: C440GX+
               Version: 727281-001
               Serial Number: INCY92700942

       Each record has:

       · A handle. This is  a  unique  identifier,  which  allows  records  to
         reference   each   other.  For  example,  processor  records  usually
         reference cache memory records using their handles.

       · A type. The SMBIOS specification defines different types of  elements
         a  computer  can  be  made  of. In this example, the type is 2, which
         means that the record contains "Base Board Information".

       · A size. Each record has a 4-byte header (2 for the handle, 1 for  the
         type,  1  for  the  size),  the rest is used by the record data. This
         value doesn’t take text strings into account (these are placed at the
         end of the record), so the actual length of the record may be (and is
         often) greater than the displayed value.

       · Decoded values. The information presented of course  depends  on  the
         type of record. Here, we learn about the board’s manufacturer, model,
         version and serial number.


       -d, --dev-mem FILE
              Read memory from device FILE (default: /dev/mem)

       -q, --quiet
              Be less verbose. Unknown, inactive and OEM-specific entries  are
              not  displayed.  Meta-data  and  handle  references  are hidden.
              Mutually exclusive with --dump.

       -s, --string KEYWORD
              Only display the value of the DMI string identified by  KEYWORD.
              KEYWORD  must be a keyword from the following list: bios-vendor,
              bios-version,  bios-release-date,  system-manufacturer,  system-
              product-name, system-version, system-serial-number, system-uuid,
              baseboard-manufacturer,    baseboard-product-name,    baseboard-
              version,  baseboard-serial-number, baseboard-asset-tag, chassis-
              manufacturer,  chassis-type,  chassis-version,   chassis-serial-
              number,    chassis-asset-tag,    processor-family,    processor-
              manufacturer,  processor-version,   processor-frequency.    Each
              keyword  corresponds  to  a  given  DMI  type and a given offset
              within this entry type.  Not all strings may  be  meaningful  or
              even  defined on all systems. Some keywords may return more than
              one result on some systems (e.g.  processor-version on a  multi-
              processor  system).   If KEYWORD is not provided or not valid, a
              list of all valid keywords is printed and dmidecode  exits  with
              an  error.   This  option  cannot  be  used  more than once, and
              implies --quiet.  Mutually exclusive with --type and --dump.

       -t, --type TYPE
              Only display the entries of type TYPE. TYPE can be either a  DMI
              type  number,  or  a  comma-separated list of type numbers, or a
              keyword  from  the  following  list:  bios,  system,  baseboard,
              chassis, processor, memory, cache, connector, slot. Refer to the
              DMI TYPES section below for details.  If  this  option  is  used
              more  than  once, the set of displayed entries will be the union
              of all the given types.  If TYPE is not provided or not valid, a
              list  of  all valid keywords is printed and dmidecode exits with
              an error.  Mutually exclusive with --string.

       -u, --dump
              Do not decode the entries, dump their  contents  as  hexadecimal
              instead.   Note that this is still a text output, no binary data
              will be thrown upon you. The strings attached to each entry  are
              displayed  as  both hexadecimal and ASCII. This option is mainly
              useful for  debugging.   Mutually  exclusive  with  --quiet  and

       -h, --help
              Display usage information and exit

       -V, --version
              Display the version and exit


       The SMBIOS specification defines the following DMI types:

       Type   Information
          0   BIOS
          1   System
          2   Base Board
          3   Chassis
          4   Processor
          5   Memory Controller
          6   Memory Module
          7   Cache
          8   Port Connector
          9   System Slots
         10   On Board Devices
         11   OEM Strings
         12   System Configuration Options

         13   BIOS Language
         14   Group Associations
         15   System Event Log
         16   Physical Memory Array
         17   Memory Device
         18   32-bit Memory Error
         19   Memory Array Mapped Address
         20   Memory Device Mapped Address
         21   Built-in Pointing Device
         22   Portable Battery
         23   System Reset
         24   Hardware Security
         25   System Power Controls
         26   Voltage Probe
         27   Cooling Device
         28   Temperature Probe
         29   Electrical Current Probe
         30   Out-of-band Remote Access
         31   Boot Integrity Services
         32   System Boot
         33   64-bit Memory Error
         34   Management Device
         35   Management Device Component
         36   Management Device Threshold Data
         37   Memory Channel
         38   IPMI Device
         39   Power Supply

       Additionally,  type 126 is used for disabled entries and type 127 is an
       end-of-table marker. Types  128  to  255  are  for  OEM-specific  data.
       dmidecode will display these entries by default, but it can only decode
       them when the vendors have contributed documentation or code for  them.

       Keywords can be used instead of type numbers with --type.  Each keyword
       is equivalent to a list of type numbers:

       Keyword     Types
       bios        0, 13
       system      1, 12, 15, 23, 32
       baseboard   2, 10
       chassis     3
       processor   4
       memory      5, 6, 16, 17
       cache       7
       connector   8
       slot        9

       Keywords are matched case-insensitively. The  following  command  lines
       are equivalent:

       · dmidecode --type 0 --type 13

       · dmidecode --type 0,13

       · dmidecode --type bios

       · dmidecode --type BIOS




       More  often  than  not,  information  contained  in  the  DMI tables is
       inaccurate, incomplete or simply wrong.


       Alan Cox, Jean Delvare


       biosdecode(8), mem(4), ownership(8), vpddecode(8)