dmidecode – DMI table decoder
Posted by Shahid 
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:
DMI TYPESThe 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
To get physical memory details, use the following commainds.
$ sudo dmidecode -t 16 # dmidecode 2.9 SMBIOS 2.4 present. Handle 0x000F, DMI type 16, 15 bytes Physical Memory Array Location: System Board Or Motherboard Use: System Memory Error Correction Type: None Maximum Capacity: 4 GB Error Information Handle: Not Provided Number Of Devices: 2
$ sudo dmidecode -t 17 # dmidecode 2.9 SMBIOS 2.4 present. Handle 0x0010, DMI type 17, 27 bytes Memory Device Array Handle: 0x000F Error Information Handle: No Error Total Width: 64 bits Data Width: 64 bits Size: 1024 MB Form Factor: SODIMM Set: 1 Locator: M1 Bank Locator: Bank 0 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz (1.5 ns) Manufacturer: Mfg 0 Serial Number: 1234-B0 Asset Tag: Not Specified Part Number: SODIMM000 Handle 0x0011, DMI type 17, 27 bytes Memory Device Array Handle: 0x000F Error Information Handle: No Error Total Width: 64 bits Data Width: 64 bits Size: 2048 MB Form Factor: SODIMM Set: 1 Locator: M2 Bank Locator: Bank 1 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz (1.5 ns) Manufacturer: Mfg 1 Serial Number: 1234-B1 Asset Tag: Not Specified Part Number: SODIMM001
