


DMIDECODE(8)                                         DMIDECODE(8)


NAME
       dmidecode - DMI table decoder

SYNOPSIS
       dmidecode [OPTIONS]


DESCRIPTION
       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 com-
       ponents, 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  evolu-
       tions  (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 Manage-
       ment 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 Informa-
       tion
               Manufacturer: Intel
               Product Name: C440GX+
               Version: 727281-001
               Serial Number: INCY92700942

       Each record has:

       o 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.

       o 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".

       o A size. Each record has a 4-byte header (2 for the  han-
         dle,  1  for the type, 1 for the size), the rest is used
         by the record data. This value doesn't take text strings



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DMIDECODE(8)                                         DMIDECODE(8)


         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.

       o 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.


OPTIONS
       -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.

       -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, chas-
              sis-asset-tag, processor-family, processor-manufac-
              turer,   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  pro-
              vided 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.

       -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.





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DMIDECODE(8)                                         DMIDECODE(8)


       -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  dis-
              played  as  both hexadecimal and ASCII. This option
              is mainly useful for debugging.

           --dump-bin FILE
              Do not decode the entries,  instead  dump  the  DMI
              data  to  a file in binary form. The generated file
              is suitable to pass to --from-dump later.

           --from-dump FILE
              Read the DMI data from  a  binary  file  previously
              generated using --dump-bin.

       -h, --help
              Display usage information and exit

       -V, --version
              Display the version and exit

       Options --string, --type and --dump-bin determine the out-
       put format and are mutually exclusive.


DMI TYPES
       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




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DMIDECODE(8)                                         DMIDECODE(8)


         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
         40   Additional Information
         41   Onboard Device

       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, 41
       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:

       o dmidecode --type 0 --type 13

       o dmidecode --type 0,13

       o dmidecode --type bios

       o dmidecode --type BIOS




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DMIDECODE(8)                                         DMIDECODE(8)


BINARY DUMP FILE FORMAT
       The binary dump files generated  by  --dump-bin  and  read
       using --from-dump are formatted as follows:

       o The SMBIOS or DMI entry point is located at offset 0x00.
         It is crafted to hard-code the table address  at  offset
         0x20.

       o The DMI table is located at offset 0x20.


FILES
       /dev/mem

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

AUTHORS
       Alan Cox, Jean Delvare

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


































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