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DMIDECODE(8)                                                      DMIDECODE(8)

       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 infor-
       mation  such as serial numbers and BIOS revision. Thanks to this table, you can retrieve this information with-
       out 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 evo-
       lutions (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 exam-
         ple, 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 ref-
              erences are hidden.

       -s, --string KEYWORD
              Only display the value of the DMI string identified by KEYWORD.  KEYWORD must be a keyword from the fol-
              lowing  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, base-
              board-version,  baseboard-serial-number,  baseboard-asset-tag, chassis-manufacturer, chassis-type, chas-
              sis-version, chassis-serial-number, chassis-asset-tag, processor-family, processor-manufacturer, proces-
              sor-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.

       -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, mem-
              ory,  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.

       -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.

           --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 output format and are mutually exclusive.

       Please note in case of dmidecode is run on a system with BIOS that boasts new SMBIOS  specification,  which  is
       not supported by the tool yet, it will print out relevant message in addition to requested data on the very top
       of the output. Thus informs the output data is not reliable.

       The SMBIOS specification defines the following DMI types:

       Type   Information
          0   BIOS
          1   System
          2   Baseboard
          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
         40   Additional Information
         41   Onboard Devices Extended Information
         42   Management Controller Host Interface

       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  num-

       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:

       ? dmidecode --type 0 --type 13

       ? dmidecode --type 0,13

       ? dmidecode --type bios

       ? dmidecode --type BIOS

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

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

       ? The DMI table is located at offset 0x20.


       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)

dmidecode                         March 2012                      DMIDECODE(8)