Using dmidecode to inspect hardware and firmware information
A practical reference for the Linux dmidecode command, including all documented `-s` keywords and `-t` DMI types with space for recording real machine output.
dmidecode is a Linux command for reading and decoding the DMI/SMBIOS tables provided by a computer’s firmware.
These tables describe hardware and platform information such as:
- system manufacturer and model
- serial numbers
- BIOS or UEFI version
- motherboard information
- CPU information
- installed and supported memory
- chassis information
- system slots
- power supplies
- temperature and voltage probes
- management interfaces
Unlike tools that actively probe hardware, dmidecode primarily reports what the system firmware has published in its SMBIOS tables. This makes querying the information relatively simple, but it also means that the information can be incomplete or incorrect if the firmware contains inaccurate data.
A complete dump can usually be obtained with:
dmidecode
On Linux, dmidecode first attempts to read the DMI tables through sysfs. If that fails, it can fall back to reading physical memory. Consequently, root privileges are often required.
This can be especially relevant inside virtual machines or containers. For example, an LXC container may not have access to:
/sys/firmware/dmi/tables/
or:
/dev/mem
In that situation dmidecode may fail even when executed as root inside the container.
The -s and -t options
Two particularly useful ways of restricting the otherwise extensive output are:
dmidecode -s KEYWORD
and:
dmidecode -t TYPE
They serve different purposes.
dmidecode -s
The -s option means string:
dmidecode -s KEYWORD
It extracts one specific value from the DMI tables.
For example:
dmidecode -s system-product-name
could return:
ProLiant DL380 Gen10
This is convenient for scripts because the command normally returns just the requested value instead of the complete DMI structure.
The available keywords can also be queried on newer versions of dmidecode with:
dmidecode --list-strings
The currently documented keywords are listed below.
dmidecode -t
The -t option means type:
dmidecode -t TYPE
Instead of extracting one individual value, it selects one or several complete SMBIOS/DMI record types.
For example:
dmidecode -t processor
returns the complete processor-related DMI records.
TYPE can either be:
- a predefined keyword such as
processor - a numeric DMI type such as
4 - a comma-separated list such as
16,17
The available symbolic type names can be displayed with:
dmidecode --list-types
Multiple -t options can also be combined:
dmidecode -t 16 -t 17
The symbolic -t keywords are essentially shortcuts for particular numeric DMI types.
-s: BIOS and platform firmware strings
All the following example outputs come from my tiny Fujitsu Esprimo Q956 Proxmox host.
bios-vendor
Command:
dmidecode -s bios-vendor
Returns the vendor of the system’s platform firmware, historically referred to as the BIOS even on modern UEFI systems.
Typical information:
- American Megatrends
- Phoenix Technologies
- Dell
- HP
- Lenovo
Output:
FUJITSU // American Megatrends Inc.
bios-version
Command:
dmidecode -s bios-version
Returns the version string of the BIOS or UEFI firmware.
This is particularly useful when checking whether a firmware update has already been installed.
Output:
V5.0.0.11 R1.33.0 for D3413-A1x
bios-release-date
Command:
dmidecode -s bios-release-date
Returns the release date recorded for the currently installed platform firmware.
Output:
09/29/2021
bios-revision
Command:
dmidecode -s bios-revision
Returns the BIOS revision encoded in the corresponding SMBIOS structure.
This may differ from the human-readable value returned by bios-version.
Output:
1.33
firmware-revision
Command:
dmidecode -s firmware-revision
Returns the revision of the system’s embedded-controller firmware, if the platform provides this information.
In dmidecode terminology, bios refers to the platform firmware while firmware in this particular keyword refers to embedded-controller firmware.
Output:
<nothing>
-s: System strings
system-manufacturer
Command:
dmidecode -s system-manufacturer
Returns the manufacturer of the complete computer.
Examples might include Dell, HP, Lenovo, Fujitsu or the manufacturer of a server platform.
Output:
FUJITSU
system-product-name
Command:
dmidecode -s system-product-name
Returns the manufacturer’s product or model name for the computer.
This is often one of the quickest ways to identify the exact server or PC model.
Output:
ESPRIMO Q956
system-version
Command:
dmidecode -s system-version
Returns the system version field supplied by the manufacturer.
Depending on the hardware, this may contain a useful revision or merely a generic placeholder.
Output:
<nothing>
system-serial-number
Command:
dmidecode -s system-serial-number
Returns the serial number assigned to the complete computer.
This can be useful for inventory management or identifying hardware in vendor support portals.
Output:
YM5G007746
system-uuid
Command:
dmidecode -s system-uuid
Returns the SMBIOS system UUID.
The value is commonly used by management software and inventory systems to uniquely identify a machine.
Output:
90237683-e111-e611-84ed-901b0e9e13f8
system-sku-number
Command:
dmidecode -s system-sku-number
Returns the system SKU supplied by the manufacturer.
The SKU may identify a particular hardware configuration within a product family.
Output:
S26361-Kxxx-Vyyy
system-family
Command:
dmidecode -s system-family
Returns the product family to which the system belongs.
For example, a vendor may use the field for a server or workstation product series.
Output:
ESPRIMO-FTS
-s: Baseboard strings
The baseboard normally represents the motherboard or system board.
baseboard-manufacturer
Command:
dmidecode -s baseboard-manufacturer
Returns the manufacturer of the motherboard or system board.
Output:
FUJITSU
baseboard-product-name
Command:
dmidecode -s baseboard-product-name
Returns the product or model name of the motherboard.
Output:
D3413-A1
baseboard-version
Command:
dmidecode -s baseboard-version
Returns the hardware version or revision of the motherboard.
Output:
S26361-D3413-A1
baseboard-serial-number
Command:
dmidecode -s baseboard-serial-number
Returns the serial number of the motherboard or system board.
Output:
49907599
baseboard-asset-tag
Command:
dmidecode -s baseboard-asset-tag
Returns the asset tag associated with the motherboard.
Whether this contains useful information depends heavily on the manufacturer and system configuration.
Output:
<nothing>
-s: Chassis strings
chassis-manufacturer
Command:
dmidecode -s chassis-manufacturer
Returns the manufacturer associated with the computer chassis.
Output:
FUJITSU
chassis-type
Command:
dmidecode -s chassis-type
Returns the general physical type of the computer enclosure.
Possible decoded values include categories such as:
- Desktop
- Tower
- Rack Mount Chassis
- Notebook
- Laptop
- Mini PC
Output:
Lunch Box
That’s funny 😂
chassis-version
Command:
dmidecode -s chassis-version
Returns the chassis version or hardware revision supplied by the manufacturer.
Output:
chassis-serial-number
Command:
dmidecode -s chassis-serial-number
Returns the chassis serial number.
Depending on the manufacturer, this may be identical to or different from system-serial-number.
Output:
<nothing>
chassis-asset-tag
Command:
dmidecode -s chassis-asset-tag
Returns an asset tag associated with the chassis.
Organizations can sometimes configure this field as part of their hardware inventory process.
Output:
<nothing>
-s: Processor strings
processor-family
Command:
dmidecode -s processor-family
Returns the processor family reported by SMBIOS.
On multi-socket systems more than one result may be returned.
Output:
Core i5
processor-manufacturer
Command:
dmidecode -s processor-manufacturer
Returns the CPU manufacturer, typically something such as Intel or AMD.
Output:
Intel(R) Corporation
processor-version
Command:
dmidecode -s processor-version
Returns the processor identification or model string.
On a system with several physical processors, the command may produce several lines because -s can match multiple DMI structures.
Output:
Intel(R) Core(TM) i5-6500T CPU @ 2.50GHz
processor-frequency
Command:
dmidecode -s processor-frequency
Returns the processor frequency stored in SMBIOS.
This is firmware-provided information and should not necessarily be interpreted as the CPU’s instantaneous operating frequency.
Output:
2800 MHz
-t: Symbolic type names
There are nine documented symbolic keywords for dmidecode -t.
-t bios
Command:
dmidecode -t bios
Equivalent DMI types:
0, 13
The bios shortcut displays information about the platform firmware and its supported languages.
It is equivalent to:
dmidecode -t 0,13
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0000, DMI type 0, 24 bytes
BIOS Information
Vendor: FUJITSU // American Megatrends Inc.
Version: V5.0.0.11 R1.33.0 for D3413-A1x
Release Date: 09/29/2021
Address: 0xF0000
Runtime Size: 64 kB
ROM Size: 16 MB
Characteristics:
PCI is supported
BIOS is upgradeable
BIOS shadowing is allowed
Boot from CD is supported
Selectable boot is supported
EDD is supported
Print screen service is supported (int 5h)
8042 keyboard services are supported (int 9h)
Serial services are supported (int 14h)
Printer services are supported (int 17h)
ACPI is supported
USB legacy is supported
BIOS boot specification is supported
Targeted content distribution is supported
UEFI is supported
BIOS Revision: 1.33
Handle 0x004E, DMI type 13, 22 bytes
BIOS Language Information
Language Description Format: Long
Installable Languages: 2
en|US|iso8859-1
ja|JP|unicode
Currently Installed Language: en|US|iso8859-1
-t system
Command:
dmidecode -t system
Equivalent DMI types:
1, 12, 15, 23, 32
This combines several structures describing the computer as a complete system, including:
- general system identification
- system configuration options
- system event log
- reset capabilities
- boot information
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0020, DMI type 12, 5 bytes
System Configuration Options
Option 1: Default string
Handle 0x0022, DMI type 32, 20 bytes
System Boot Information
Status: No errors detected
Handle 0x0043, DMI type 1, 27 bytes
System Information
Manufacturer: FUJITSU
Product Name: ESPRIMO Q956
Version:
Serial Number: YM5G007746
UUID: 90237683-e111-e611-84ed-901b0e9e13f8
Wake-up Type: Other
SKU Number: S26361-Kxxx-Vyyy
Family: ESPRIMO-FTS
Handle 0x0045, DMI type 15, 77 bytes
System Event Log
Area Length: 16383 bytes
Header Start Offset: 0x0000
Header Length: 16 bytes
Data Start Offset: 0x0010
Access Method: Memory-mapped physical 32-bit address
Access Address: 0xFF860000
Status: Valid, Not Full
Change Token: 0x0000004C
Header Format: Type 1
Supported Log Type Descriptors: 27
Descriptor 1: Single-bit ECC memory error
Data Format 1: Multiple-event handle
Descriptor 2: Multi-bit ECC memory error
Data Format 2: Multiple-event handle
Descriptor 3: Parity memory error
Data Format 3: None
Descriptor 4: Bus timeout
Data Format 4: None
Descriptor 5: I/O channel block
Data Format 5: None
Descriptor 6: Software NMI
Data Format 6: None
Descriptor 7: POST memory resize
Data Format 7: None
Descriptor 8: POST error
Data Format 8: POST results bitmap
Descriptor 9: PCI parity error
Data Format 9: Multiple-event handle
Descriptor 10: PCI system error
Data Format 10: Multiple-event handle
Descriptor 11: CPU failure
Data Format 11: None
Descriptor 12: EISA failsafe timer timeout
Data Format 12: None
Descriptor 13: Correctable memory log disabled
Data Format 13: None
Descriptor 14: Logging disabled
Data Format 14: None
Descriptor 15: System limit exceeded
Data Format 15: None
Descriptor 16: Asynchronous hardware timer expired
Data Format 16: None
Descriptor 17: System configuration information
Data Format 17: None
Descriptor 18: Hard disk information
Data Format 18: None
Descriptor 19: System reconfigured
Data Format 19: None
Descriptor 20: Uncorrectable CPU-complex error
Data Format 20: None
Descriptor 21: Log area reset/cleared
Data Format 21: None
Descriptor 22: System boot
Data Format 22: None
Descriptor 23: End of log
Data Format 23: None
Descriptor 24: OEM-specific
Data Format 24: OEM-specific
Descriptor 25: OEM-specific
Data Format 25: OEM-specific
Descriptor 26: OEM-specific
Data Format 26: OEM-specific
Descriptor 27: OEM-specific
Data Format 27: OEM-specific
-t baseboard
Command:
dmidecode -t baseboard
Equivalent DMI types:
2, 10, 41
Displays information associated with the motherboard and onboard devices.
Output:
-t chassis
Command:
dmidecode -t chassis
Equivalent DMI type:
3
Displays information describing the physical enclosure of the machine.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x001E, DMI type 10, 6 bytes
On Board Device Information
Type: Video
Status: Enabled
Description: Not defined see Type 41.
Handle 0x0028, DMI type 41, 11 bytes
Onboard Device
Reference Designation: Nuvoton NCT6792 Super I/O
Type: Other
Status: Enabled
Type Instance: 1
Bus Address: 00ff:ff:1f.7
Handle 0x0029, DMI type 41, 11 bytes
Onboard Device
Reference Designation: Realtek ALC671
Type: Sound
Status: Enabled
Type Instance: 1
Bus Address: 00ff:ff:1f.7
Handle 0x002A, DMI type 41, 11 bytes
Onboard Device
Reference Designation: PCH Q170
Type: Video
Status: Enabled
Type Instance: 1
Bus Address: 00ff:ff:1f.7
Handle 0x002B, DMI type 41, 11 bytes
Onboard Device
Reference Designation: Teutates
Type: Other
Status: Enabled
Type Instance: 1
Bus Address: 00ff:ff:1f.7
Handle 0x002C, DMI type 41, 11 bytes
Onboard Device
Reference Designation: Intel I219LM
Type: Ethernet
Status: Enabled
Type Instance: 1
Bus Address: 00ff:ff:1f.7
Handle 0x0040, DMI type 2, 15 bytes
Base Board Information
Manufacturer: FUJITSU
Product Name: D3413-A1
Version: S26361-D3413-A1
Serial Number: 49907599
Asset Tag:
Features:
Board is a hosting board
Board is replaceable
Location In Chassis:
Chassis Handle: 0x0003
Type: Motherboard
Contained Object Handles: 0
-t processor
Command:
dmidecode -t processor
Equivalent DMI type:
4
Displays processor structures, potentially including:
- socket
- CPU family
- manufacturer
- CPU model
- voltage
- maximum speed
- current speed
- core count
- thread count
- cache references
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0031, DMI type 4, 48 bytes
Processor Information
Socket Designation: CPU1
Type: Central Processor
Family: Core i5
Manufacturer: Intel(R) Corporation
ID: E3 06 05 00 FF FB EB BF
Signature: Type 0, Family 6, Model 94, Stepping 3
Flags:
FPU (Floating-point unit on-chip)
VME (Virtual mode extension)
DE (Debugging extension)
PSE (Page size extension)
TSC (Time stamp counter)
MSR (Model specific registers)
PAE (Physical address extension)
MCE (Machine check exception)
CX8 (CMPXCHG8 instruction supported)
APIC (On-chip APIC hardware supported)
SEP (Fast system call)
MTRR (Memory type range registers)
PGE (Page global enable)
MCA (Machine check architecture)
CMOV (Conditional move instruction supported)
PAT (Page attribute table)
PSE-36 (36-bit page size extension)
CLFSH (CLFLUSH instruction supported)
DS (Debug store)
ACPI (ACPI supported)
MMX (MMX technology supported)
FXSR (FXSAVE and FXSTOR instructions supported)
SSE (Streaming SIMD extensions)
SSE2 (Streaming SIMD extensions 2)
SS (Self-snoop)
HTT (Multi-threading)
TM (Thermal monitor supported)
PBE (Pending break enabled)
Version: Intel(R) Core(TM) i5-6500T CPU @ 2.50GHz
Voltage: 1.0 V
External Clock: 100 MHz
Max Speed: 8300 MHz
Current Speed: 2800 MHz
Status: Populated, Enabled
Upgrade: Other
L1 Cache Handle: 0x002E
L2 Cache Handle: 0x002F
L3 Cache Handle: 0x0030
Serial Number:
Asset Tag:
Part Number:
Core Count: 4
Core Enabled: 4
Thread Count: 4
Characteristics:
64-bit capable
Multi-Core
Execute Protection
Enhanced Virtualization
Power/Performance Control
-t memory
Command:
dmidecode -t memory
Equivalent DMI types:
5, 6, 16, 17
Displays memory-related structures.
Particularly useful are types 16 and 17, which describe the memory array and individual DIMMs respectively.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0032, DMI type 16, 23 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: None
Maximum Capacity: 64 GB
Error Information Handle: Not Provided
Number Of Devices: 4
Handle 0x0033, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 8 GB
Form Factor: SODIMM
Set: None
Locator: DIMM CHA3
Bank Locator: BANK 0
Type: DDR4
Type Detail: Synchronous
Speed: 2133 MT/s
Manufacturer: SK Hynix
Serial Number: 25F3E2BD
Asset Tag: 1605
Part Number: HMA41GS6AFR8N-TF
Rank: 2
Configured Memory Speed: 2133 MT/s
Minimum Voltage: Unknown
Maximum Voltage: Unknown
Configured Voltage: 1.2 V
Handle 0x0034, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: Not Provided
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: Unknown
Set: None
Locator: DIMM CHA1
Bank Locator: BANK 1
Type: Unknown
Type Detail: None
Handle 0x0035, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 8 GB
Form Factor: SODIMM
Set: None
Locator: DIMM CHB4
Bank Locator: BANK 2
Type: DDR4
Type Detail: Synchronous
Speed: 2133 MT/s
Manufacturer: SK Hynix
Serial Number: 25F3E2B6
Asset Tag: 1605
Part Number: HMA41GS6AFR8N-TF
Rank: 2
Configured Memory Speed: 2133 MT/s
Minimum Voltage: Unknown
Maximum Voltage: Unknown
Configured Voltage: 1.2 V
Handle 0x0036, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: Not Provided
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: Unknown
Set: None
Locator: DIMM CHB2
Bank Locator: BANK 3
Type: Unknown
Type Detail: None
-t cache
Command:
dmidecode -t cache
Equivalent DMI type:
7
Displays CPU cache structures such as L1, L2 and L3 caches when exposed through SMBIOS.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x002D, DMI type 7, 19 bytes
Cache Information
Socket Designation: L1 Cache
Configuration: Enabled, Not Socketed, Level 1
Operational Mode: Write Through
Location: Internal
Installed Size: 128 kB
Maximum Size: 128 kB
Supported SRAM Types:
Unknown
Installed SRAM Type: Unknown
Speed: Unknown
Error Correction Type: Unknown
System Type: Data
Associativity: 8-way Set-associative
Handle 0x002E, DMI type 7, 19 bytes
Cache Information
Socket Designation: L1 Cache
Configuration: Enabled, Not Socketed, Level 1
Operational Mode: Write Through
Location: Internal
Installed Size: 128 kB
Maximum Size: 128 kB
Supported SRAM Types:
Unknown
Installed SRAM Type: Unknown
Speed: Unknown
Error Correction Type: Unknown
System Type: Instruction
Associativity: 8-way Set-associative
Handle 0x002F, DMI type 7, 19 bytes
Cache Information
Socket Designation: L2 Cache
Configuration: Enabled, Not Socketed, Level 2
Operational Mode: Write Through
Location: Internal
Installed Size: 1 MB
Maximum Size: 1 MB
Supported SRAM Types:
Unknown
Installed SRAM Type: Unknown
Speed: Unknown
Error Correction Type: Single-bit ECC
System Type: Unified
Associativity: 4-way Set-associative
Handle 0x0030, DMI type 7, 19 bytes
Cache Information
Socket Designation: L3 Cache
Configuration: Enabled, Not Socketed, Level 3
Operational Mode: Write Back
Location: Internal
Installed Size: 6 MB
Maximum Size: 6 MB
Supported SRAM Types:
Unknown
Installed SRAM Type: Unknown
Speed: Unknown
Error Correction Type: Single-bit ECC
System Type: Unified
Associativity: 12-way Set-associative
-t connector
Command:
dmidecode -t connector
Equivalent DMI type:
8
Displays information about physical port connectors provided by the machine.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0004, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Nuvoton
Internal Connector Type: None
External Reference Designator: PS/2 Mouse
External Connector Type: PS/2
Port Type: Mouse Port
Handle 0x0005, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Nuvoton
Internal Connector Type: None
External Reference Designator: PS/2 Keyboard
External Connector Type: PS/2
Port Type: Keyboard Port
Handle 0x0006, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Nuvoton
Internal Connector Type: 9 Pin Dual Inline (pin 10 cut)
External Reference Designator: Serial-1
External Connector Type: None
Port Type: Serial Port 16550 Compatible
Handle 0x0007, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: LAN I219LM
Internal Connector Type: None
External Reference Designator: LAN 0
External Connector Type: RJ-45
Port Type: Network Port
Handle 0x0008, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB Q170
Internal Connector Type: Proprietary
External Reference Designator: USB
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0009, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB FRONT
Internal Connector Type: Proprietary
External Reference Designator: Front: USB-0
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000A, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB FRONT
Internal Connector Type: Proprietary
External Reference Designator: Front: USB-1
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000B, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-2
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000C, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-3
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000D, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-4
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000E, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-5
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000F, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-6
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0010, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-7
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0011, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB INTERN
Internal Connector Type: Proprietary
External Reference Designator: Intern: USB-9
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0012, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 FRONT
Internal Connector Type: Proprietary
External Reference Designator: Front: USB 1
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0013, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 FRONT
Internal Connector Type: Proprietary
External Reference Designator: Front: USB 2
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0014, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB 3
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0015, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB 4
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0016, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB 7
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0017, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB 8
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0018, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: PCH Q170
Internal Connector Type: SAS/SATA Plug Receptacle
External Reference Designator: SATA-0
External Connector Type: None
Port Type: None
Handle 0x0019, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: PCH Q170
Internal Connector Type: SAS/SATA Plug Receptacle
External Reference Designator: SATA-1
External Connector Type: None
Port Type: None
Handle 0x001A, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Intel
Internal Connector Type: None
External Reference Designator: DP 1.2
External Connector Type: Other
Port Type: Video Port
Handle 0x001B, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Intel
Internal Connector Type: None
External Reference Designator: DP 1.2
External Connector Type: Other
Port Type: Video Port
Handle 0x001C, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Intel
Internal Connector Type: None
External Reference Designator: DVI-D
External Connector Type: Other
Port Type: Video Port
-t slot
Command:
dmidecode -t slot
Equivalent DMI type:
9
Displays information about system expansion slots such as PCI and PCI Express slots.
This can be particularly useful on servers for identifying:
- slot designation
- slot type
- slot width
- whether a slot is in use
- bus address
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x001D, DMI type 9, 17 bytes
System Slot Information
Designation: J6B2
Type: Unknown
Current Usage: In Use
Length: Unknown
Characteristics: Unknown
Bus Address: 0000:00:01.0
Numeric DMI types
Instead of using symbolic keywords, dmidecode -t can query individual SMBIOS structure types directly.
For example:
dmidecode -t 17
is a particularly useful command because type 17 represents individual memory devices.
The standard types currently documented by dmidecode range from 0 through 42. Types 126 and 127 have special meanings, while 128 through 255 are reserved for OEM-specific data.
Type 0 — Platform Firmware
Command:
dmidecode -t 0
Contains information about the platform firmware, historically referred to as BIOS information.
Typical fields include:
- vendor
- version
- release date
- ROM size
- supported characteristics
- firmware revisions
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0000, DMI type 0, 24 bytes
BIOS Information
Vendor: FUJITSU // American Megatrends Inc.
Version: V5.0.0.11 R1.33.0 for D3413-A1x
Release Date: 09/29/2021
Address: 0xF0000
Runtime Size: 64 kB
ROM Size: 16 MB
Characteristics:
PCI is supported
BIOS is upgradeable
BIOS shadowing is allowed
Boot from CD is supported
Selectable boot is supported
EDD is supported
Print screen service is supported (int 5h)
8042 keyboard services are supported (int 9h)
Serial services are supported (int 14h)
Printer services are supported (int 17h)
ACPI is supported
USB legacy is supported
BIOS boot specification is supported
Targeted content distribution is supported
UEFI is supported
BIOS Revision: 1.33
Type 1 — System
Command:
dmidecode -t 1
Describes the computer as a complete system.
Typical fields include:
- manufacturer
- product name
- version
- serial number
- UUID
- SKU
- family
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0043, DMI type 1, 27 bytes
System Information
Manufacturer: FUJITSU
Product Name: ESPRIMO Q956
Version:
Serial Number: YM5G007746
UUID: 90237683-e111-e611-84ed-901b0e9e13f8
Wake-up Type: Other
SKU Number: S26361-Kxxx-Vyyy
Family: ESPRIMO-FTS
Type 2 — Baseboard
Command:
dmidecode -t 2
Describes the motherboard or system board.
Typical fields include:
-Hi! manufacturer -Hi! product name -Hi! version -Hi! serial number -Hi! asset tag -Hi! board type
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0040, DMI type 2, 15 bytes
Base Board Information
Manufacturer: FUJITSU
Product Name: D3413-A1
Version: S26361-D3413-A1
Serial Number: 49907599
Asset Tag:
Features:
Board is a hosting board
Board is replaceable
Location In Chassis:
Chassis Handle: 0x0003
Type: Motherboard
Contained Object Handles: 0
Type 3 — Chassis
Command:
dmidecode -t 3
Describes the system enclosure or chassis.
Typical information includes chassis type, manufacturer, serial number and asset information.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0041, DMI type 3, 22 bytes
Chassis Information
Manufacturer: FUJITSU
Type: Lunch Box
Lock: Not Present
Version:
Serial Number: YM5G007746
Asset Tag:
Boot-up State: Safe
Power Supply State: Safe
Thermal State: Safe
Security Status: None
OEM Information: 0x00000000
Height: Unspecified
Number Of Power Cords: 1
Contained Elements: 0
SKU Number: Default string
Type 4 — Processor
Command:
dmidecode -t 4
Contains information about installed processor sockets and processors.
This is one of the most useful DMI types for examining CPU information.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0031, DMI type 4, 48 bytes
Processor Information
Socket Designation: CPU1
Type: Central Processor
Family: Core i5
Manufacturer: Intel(R) Corporation
ID: E3 06 05 00 FF FB EB BF
Signature: Type 0, Family 6, Model 94, Stepping 3
Flags:
FPU (Floating-point unit on-chip)
VME (Virtual mode extension)
DE (Debugging extension)
PSE (Page size extension)
TSC (Time stamp counter)
MSR (Model specific registers)
PAE (Physical address extension)
MCE (Machine check exception)
CX8 (CMPXCHG8 instruction supported)
APIC (On-chip APIC hardware supported)
SEP (Fast system call)
MTRR (Memory type range registers)
PGE (Page global enable)
MCA (Machine check architecture)
CMOV (Conditional move instruction supported)
PAT (Page attribute table)
PSE-36 (36-bit page size extension)
CLFSH (CLFLUSH instruction supported)
DS (Debug store)
ACPI (ACPI supported)
MMX (MMX technology supported)
FXSR (FXSAVE and FXSTOR instructions supported)
SSE (Streaming SIMD extensions)
SSE2 (Streaming SIMD extensions 2)
SS (Self-snoop)
HTT (Multi-threading)
TM (Thermal monitor supported)
PBE (Pending break enabled)
Version: Intel(R) Core(TM) i5-6500T CPU @ 2.50GHz
Voltage: 1.0 V
External Clock: 100 MHz
Max Speed: 8300 MHz
Current Speed: 2800 MHz
Status: Populated, Enabled
Upgrade: Other
L1 Cache Handle: 0x002E
L2 Cache Handle: 0x002F
L3 Cache Handle: 0x0030
Serial Number:
Asset Tag:
Part Number:
Core Count: 4
Core Enabled: 4
Thread Count: 4
Characteristics:
64-bit capable
Multi-Core
Execute Protection
Enhanced Virtualization
Power/Performance Control
Type 5 — Memory Controller
Command:
dmidecode -t 5
Describes legacy memory-controller information.
This SMBIOS structure is mainly relevant to older systems.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 6 — Memory Module
Command:
dmidecode -t 6
Describes legacy memory-module structures.
Modern systems generally expose memory through types 16 and 17 instead.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present
Type 7 — Cache
Command:
dmidecode -t 7
Describes processor cache structures.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x002D, DMI type 7, 19 bytes
Cache Information
Socket Designation: L1 Cache
Configuration: Enabled, Not Socketed, Level 1
Operational Mode: Write Through
Location: Internal
Installed Size: 128 kB
Maximum Size: 128 kB
Supported SRAM Types:
Unknown
Installed SRAM Type: Unknown
Speed: Unknown
Error Correction Type: Unknown
System Type: Data
Associativity: 8-way Set-associative
Handle 0x002E, DMI type 7, 19 bytes
Cache Information
Socket Designation: L1 Cache
Configuration: Enabled, Not Socketed, Level 1
Operational Mode: Write Through
Location: Internal
Installed Size: 128 kB
Maximum Size: 128 kB
Supported SRAM Types:
Unknown
Installed SRAM Type: Unknown
Speed: Unknown
Error Correction Type: Unknown
System Type: Instruction
Associativity: 8-way Set-associative
Handle 0x002F, DMI type 7, 19 bytes
Cache Information
Socket Designation: L2 Cache
Configuration: Enabled, Not Socketed, Level 2
Operational Mode: Write Through
Location: Internal
Installed Size: 1 MB
Maximum Size: 1 MB
Supported SRAM Types:
Unknown
Installed SRAM Type: Unknown
Speed: Unknown
Error Correction Type: Single-bit ECC
System Type: Unified
Associativity: 4-way Set-associative
Handle 0x0030, DMI type 7, 19 bytes
Cache Information
Socket Designation: L3 Cache
Configuration: Enabled, Not Socketed, Level 3
Operational Mode: Write Back
Location: Internal
Installed Size: 6 MB
Maximum Size: 6 MB
Supported SRAM Types:
Unknown
Installed SRAM Type: Unknown
Speed: Unknown
Error Correction Type: Single-bit ECC
System Type: Unified
Associativity: 12-way Set-associative
Type 8 — Port Connector
Command:
dmidecode -t 8
Describes internal and external physical connectors.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0004, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Nuvoton
Internal Connector Type: None
External Reference Designator: PS/2 Mouse
External Connector Type: PS/2
Port Type: Mouse Port
Handle 0x0005, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Nuvoton
Internal Connector Type: None
External Reference Designator: PS/2 Keyboard
External Connector Type: PS/2
Port Type: Keyboard Port
Handle 0x0006, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Nuvoton
Internal Connector Type: 9 Pin Dual Inline (pin 10 cut)
External Reference Designator: Serial-1
External Connector Type: None
Port Type: Serial Port 16550 Compatible
Handle 0x0007, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: LAN I219LM
Internal Connector Type: None
External Reference Designator: LAN 0
External Connector Type: RJ-45
Port Type: Network Port
Handle 0x0008, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB Q170
Internal Connector Type: Proprietary
External Reference Designator: USB
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0009, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB FRONT
Internal Connector Type: Proprietary
External Reference Designator: Front: USB-0
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000A, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB FRONT
Internal Connector Type: Proprietary
External Reference Designator: Front: USB-1
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000B, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-2
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000C, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-3
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000D, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-4
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000E, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-5
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x000F, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-6
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0010, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB-7
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0011, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB INTERN
Internal Connector Type: Proprietary
External Reference Designator: Intern: USB-9
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0012, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 FRONT
Internal Connector Type: Proprietary
External Reference Designator: Front: USB 1
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0013, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 FRONT
Internal Connector Type: Proprietary
External Reference Designator: Front: USB 2
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0014, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB 3
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0015, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB 4
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0016, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB 7
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0017, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: USB 3.0 REAR
Internal Connector Type: Proprietary
External Reference Designator: Rear: USB 8
External Connector Type: Access Bus (USB)
Port Type: USB
Handle 0x0018, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: PCH Q170
Internal Connector Type: SAS/SATA Plug Receptacle
External Reference Designator: SATA-0
External Connector Type: None
Port Type: None
Handle 0x0019, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: PCH Q170
Internal Connector Type: SAS/SATA Plug Receptacle
External Reference Designator: SATA-1
External Connector Type: None
Port Type: None
Handle 0x001A, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Intel
Internal Connector Type: None
External Reference Designator: DP 1.2
External Connector Type: Other
Port Type: Video Port
Handle 0x001B, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Intel
Internal Connector Type: None
External Reference Designator: DP 1.2
External Connector Type: Other
Port Type: Video Port
Handle 0x001C, DMI type 8, 9 bytes
Port Connector Information
Internal Reference Designator: Intel
Internal Connector Type: None
External Reference Designator: DVI-D
External Connector Type: Other
Port Type: Video Port
Type 9 — System Slots
Command:
dmidecode -t 9
Describes expansion slots such as PCI or PCI Express slots.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x001D, DMI type 9, 17 bytes
System Slot Information
Designation: J6B2
Type: Unknown
Current Usage: In Use
Length: Unknown
Characteristics: Unknown
Bus Address: 0000:00:01.0
Type 10 — On Board Devices
Command:
dmidecode -t 10
Describes devices integrated directly onto the system board.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x001E, DMI type 10, 6 bytes
On Board Device Information
Type: Video
Status: Enabled
Description: Not defined see Type 41.
Type 11 — OEM Strings
Command:
dmidecode -t 11
Contains arbitrary strings supplied by the system manufacturer.
Their interpretation is vendor-specific.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x001F, DMI type 11, 5 bytes
OEM Strings
String 1: FUJITSU
String 2: FUJITSU
String 3: FUJITSU TECHNOLOGY SOLUTIONS
Type 12 — System Configuration Options
Command:
dmidecode -t 12
Contains textual configuration information supplied by the system manufacturer.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0020, DMI type 12, 5 bytes
System Configuration Options
Option 1: Default string
Type 13 — Firmware Language
Command:
dmidecode -t 13
Describes languages supported by the platform firmware.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x004E, DMI type 13, 22 bytes
BIOS Language Information
Language Description Format: Long
Installable Languages: 2
en|US|iso8859-1
ja|JP|unicode
Currently Installed Language: en|US|iso8859-1
Type 14 — Group Associations
Command:
dmidecode -t 14
Associates several SMBIOS structures with a logical group.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x004D, DMI type 14, 20 bytes
Group Associations
Name: Firmware Version Info
Items: 5
0x0048 (OEM-specific)
0x0049 (OEM-specific)
0x004A (OEM-specific)
0x004B (OEM-specific)
0x004C (OEM-specific)
Handle 0x004F, DMI type 14, 8 bytes
Group Associations
Name: $MEI
Items: 1
0x0000 (OEM-specific)
Type 15 — System Event Log
Command:
dmidecode -t 15
Describes the firmware-provided system event log and its capabilities.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0045, DMI type 15, 77 bytes
System Event Log
Area Length: 16383 bytes
Header Start Offset: 0x0000
Header Length: 16 bytes
Data Start Offset: 0x0010
Access Method: Memory-mapped physical 32-bit address
Access Address: 0xFF860000
Status: Valid, Not Full
Change Token: 0x0000004C
Header Format: Type 1
Supported Log Type Descriptors: 27
Descriptor 1: Single-bit ECC memory error
Data Format 1: Multiple-event handle
Descriptor 2: Multi-bit ECC memory error
Data Format 2: Multiple-event handle
Descriptor 3: Parity memory error
Data Format 3: None
Descriptor 4: Bus timeout
Data Format 4: None
Descriptor 5: I/O channel block
Data Format 5: None
Descriptor 6: Software NMI
Data Format 6: None
Descriptor 7: POST memory resize
Data Format 7: None
Descriptor 8: POST error
Data Format 8: POST results bitmap
Descriptor 9: PCI parity error
Data Format 9: Multiple-event handle
Descriptor 10: PCI system error
Data Format 10: Multiple-event handle
Descriptor 11: CPU failure
Data Format 11: None
Descriptor 12: EISA failsafe timer timeout
Data Format 12: None
Descriptor 13: Correctable memory log disabled
Data Format 13: None
Descriptor 14: Logging disabled
Data Format 14: None
Descriptor 15: System limit exceeded
Data Format 15: None
Descriptor 16: Asynchronous hardware timer expired
Data Format 16: None
Descriptor 17: System configuration information
Data Format 17: None
Descriptor 18: Hard disk information
Data Format 18: None
Descriptor 19: System reconfigured
Data Format 19: None
Descriptor 20: Uncorrectable CPU-complex error
Data Format 20: None
Descriptor 21: Log area reset/cleared
Data Format 21: None
Descriptor 22: System boot
Data Format 22: None
Descriptor 23: End of log
Data Format 23: None
Descriptor 24: OEM-specific
Data Format 24: OEM-specific
Descriptor 25: OEM-specific
Data Format 25: OEM-specific
Descriptor 26: OEM-specific
Data Format 26: OEM-specific
Descriptor 27: OEM-specific
Data Format 27: OEM-specific
Type 16 — Physical Memory Array
Command:
dmidecode -t 16
Describes a physical memory array.
This often contains particularly useful information such as:
- location
- intended use
- error correction
- maximum memory capacity
- number of memory devices
For determining how much RAM a machine can theoretically support, this is one of the first types worth checking.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0032, DMI type 16, 23 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: None
Maximum Capacity: 64 GB
Error Information Handle: Not Provided
Number Of Devices: 4
Type 17 — Memory Device
Command:
dmidecode -t 17
Describes individual memory devices or DIMM slots.
Typical information includes:
- slot locator
- installed size
- memory type
- speed
- configured speed
- manufacturer
- serial number
- part number
- rank
For examining installed RAM, this is generally the most useful dmidecode type.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0033, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 8 GB
Form Factor: SODIMM
Set: None
Locator: DIMM CHA3
Bank Locator: BANK 0
Type: DDR4
Type Detail: Synchronous
Speed: 2133 MT/s
Manufacturer: SK Hynix
Serial Number: 25F3E2BD
Asset Tag: 1605
Part Number: HMA41GS6AFR8N-TF
Rank: 2
Configured Memory Speed: 2133 MT/s
Minimum Voltage: Unknown
Maximum Voltage: Unknown
Configured Voltage: 1.2 V
Handle 0x0034, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: Not Provided
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: Unknown
Set: None
Locator: DIMM CHA1
Bank Locator: BANK 1
Type: Unknown
Type Detail: None
Handle 0x0035, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 8 GB
Form Factor: SODIMM
Set: None
Locator: DIMM CHB4
Bank Locator: BANK 2
Type: DDR4
Type Detail: Synchronous
Speed: 2133 MT/s
Manufacturer: SK Hynix
Serial Number: 25F3E2B6
Asset Tag: 1605
Part Number: HMA41GS6AFR8N-TF
Rank: 2
Configured Memory Speed: 2133 MT/s
Minimum Voltage: Unknown
Maximum Voltage: Unknown
Configured Voltage: 1.2 V
Handle 0x0036, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0032
Error Information Handle: Not Provided
Total Width: Unknown
Data Width: Unknown
Size: No Module Installed
Form Factor: Unknown
Set: None
Locator: DIMM CHB2
Bank Locator: BANK 3
Type: Unknown
Type Detail: None
Type 18 — 32-bit Memory Error
Command:
dmidecode -t 18
Contains information about 32-bit memory-error conditions.
This structure primarily exists for compatibility with older SMBIOS implementations.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 19 — Memory Array Mapped Address
Command:
dmidecode -t 19
Describes the address range mapped to a physical memory array.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0037, DMI type 19, 31 bytes
Memory Array Mapped Address
Starting Address: 0x00000000000
Ending Address: 0x003FFFFFFFF
Range Size: 16 GB
Physical Array Handle: 0x0032
Partition Width: 2
Type 20 — Memory Device Mapped Address
Command:
dmidecode -t 20
Maps an individual memory device to an address range.
It can connect information about a DIMM with the corresponding region in the system’s physical address space.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 21 — Built-in Pointing Device
Command:
dmidecode -t 21
Describes an integrated pointing device such as a touchpad, trackball or similar device.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 22 — Portable Battery
Command:
dmidecode -t 22
Describes a system’s built-in battery.
This is primarily relevant for laptops and other portable computers.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 23 — System Reset
Command:
dmidecode -t 23
Describes hardware or firmware system-reset capabilities and watchdog-related settings.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.I'm
Type 24 — Hardware Security
Command:
dmidecode -t 24
Describes certain hardware-security settings reported by SMBIOS.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0021, DMI type 24, 5 bytes
Hardware Security
Power-On Password Status: Disabled
Keyboard Password Status: Not Implemented
Administrator Password Status: Disabled
Front Panel Reset Status: Not Implemented
Type 25 — System Power Controls
Command:
dmidecode -t 25
Describes scheduled or firmware-controlled system power operations.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 26 — Voltage Probe
Command:
dmidecode -t 26
Describes voltage monitoring probes known to the firmware.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0023, DMI type 26, 22 bytes
Voltage Probe
Description: LM78A
Location: Power Unit
Status: OK
Maximum Value: Unknown
Minimum Value: Unknown
Resolution: Unknown
Tolerance: Unknown
Accuracy: Unknown
OEM-specific Information: 0x00000000
Nominal Value: Unknown
Type 27 — Cooling Device
Command:
dmidecode -t 27
Describes cooling devices such as system fans.
Output:
Cooling Device
Temperature Probe Handle: 0x0024
Type: Power Supply Fan
Status: OK
Cooling Unit Group: 1
OEM-specific Information: 0x00000000
Nominal Speed: Unknown Or Non-rotating
Description: Cooling Dev 1
Type 28 — Temperature Probe
Command:
dmidecode -t 28
Describes temperature sensors reported through SMBIOS.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0024, DMI type 28, 22 bytes
Temperature Probe
Description: LM78A
Location: Power Unit
Status: OK
Maximum Value: Unknown
Minimum Value: Unknown
Resolution: Unknown
Tolerance: Unknown
Accuracy: Unknown
OEM-specific Information: 0x00000000
Nominal Value: Unknown
Type 29 — Electrical Current Probe
Command:
dmidecode -t 29
Describes electrical-current monitoring devices.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0026, DMI type 29, 22 bytes
Electrical Current Probe
Description: ABC
Location: Power Unit
Status: OK
Maximum Value: Unknown
Minimum Value: Unknown
Resolution: Unknown
Tolerance: Unknown
Accuracy: Unknown
OEM-specific Information: 0x00000000
Nominal Value: Unknown
Type 30 — Out-of-band Remote Access
Command:
dmidecode -t 30
Describes firmware-supported out-of-band remote-access facilities.
This can be relevant on server-class hardware with dedicated management capabilities.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 31 — Boot Integrity Services
Command:
dmidecode -t 31
Contains information related to SMBIOS Boot Integrity Services.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 32 — System Boot
Command:
dmidecode -t 32
Describes the system’s boot status as reported by the firmware.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0022, DMI type 32, 20 bytes
System Boot Information
Status: No errors detected
Type 33 — 64-bit Memory Error
Command:
dmidecode -t 33
Contains extended memory-error information using 64-bit address fields.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 34 — Management Device
Command:
dmidecode -t 34
Describes a system management device.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 35 — Management Device Component
Command:
dmidecode -t 35
Associates a management device with a particular hardware component.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 36 — Management Device Threshold Data
Command:
dmidecode -t 36
Contains threshold information associated with system management devices.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 37 — Memory Channel
Command:
dmidecode -t 37
Describes memory-channel organization and the devices belonging to a particular channel.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 38 — IPMI Device
Command:
dmidecode -t 38
Describes an Intelligent Platform Management Interface (IPMI) controller.
This is particularly relevant for server hardware with a Baseboard Management Controller.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 39 — Power Supply
Command:
dmidecode -t 39
Describes system power supplies.
On servers this may expose information about individual redundant power-supply units.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0027, DMI type 39, 22 bytes
System Power Supply
Power Unit Group: 1
Location: To Be Filled By O.E.M.
Name: To Be Filled By O.E.M.
Manufacturer: To Be Filled By O.E.M.
Serial Number: To Be Filled By O.E.M.
Asset Tag: To Be Filled By O.E.M.
Model Part Number: To Be Filled By O.E.M.
Revision: To Be Filled By O.E.M.
Max Power Capacity: Unknown
Status: Present, OK
Type: Switching
Input Voltage Range Switching: Auto-switch
Plugged: Yes
Hot Replaceable: No
Input Voltage Probe Handle: 0x0023
Cooling Device Handle: 0x0025
Input Current Probe Handle: 0x0026
Type 40 — Additional Information
Command:
dmidecode -t 40
Provides additional information referencing fields of other SMBIOS structures.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 41 — Onboard Devices Extended Information
Command:
dmidecode -t 41
Provides an extended description of onboard devices.
It supplements the older type 10 structure.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0028, DMI type 41, 11 bytes
Onboard Device
Reference Designation: Nuvoton NCT6792 Super I/O
Type: Other
Status: Enabled
Type Instance: 1
Bus Address: 00ff:ff:1f.7
Handle 0x0029, DMI type 41, 11 bytes
Onboard Device
Reference Designation: Realtek ALC671
Type: Sound
Status: Enabled
Type Instance: 1
Bus Address: 00ff:ff:1f.7
Handle 0x002A, DMI type 41, 11 bytes
Onboard Device
Reference Designation: PCH Q170
Type: Video
Status: Enabled
Type Instance: 1
Bus Address: 00ff:ff:1f.7
Handle 0x002B, DMI type 41, 11 bytes
Onboard Device
Reference Designation: Teutates
Type: Other
Status: Enabled
Type Instance: 1
Bus Address: 00ff:ff:1f.7
Handle 0x002C, DMI type 41, 11 bytes
Onboard Device
Reference Designation: Intel I219LM
Type: Ethernet
Status: Enabled
Type Instance: 1
Bus Address: 00ff:ff:1f.7
Type 42 — Management Controller Host Interface
Command:
dmidecode -t 42
Describes the interface between the operating system and a platform management controller.
This can be particularly relevant on server platforms equipped with dedicated management controllers.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 126 — Inactive or disabled entry
Command:
dmidecode -t 126
Type 126 is reserved for SMBIOS structures that have been marked inactive or disabled.
There will normally be little reason to request this type during ordinary hardware inventory.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Type 127 — End-of-table marker
Command:
dmidecode -t 127
Type 127 marks the end of the SMBIOS structure table.
It does not represent a physical hardware component.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x0051, DMI type 127, 4 bytes
End Of Table
Types 128–255 — OEM-specific structures
Numeric values from 128 through 255 are reserved for manufacturer-specific SMBIOS structures.
For example:
dmidecode -t 128
or:
dmidecode -t 200
Whether these types exist and whether dmidecode can decode them depends entirely on the hardware manufacturer. dmidecode can only provide a meaningful decoded representation when sufficient vendor-specific information is known by the tool.
Output:
# dmidecode 3.4
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.
Handle 0x003B, DMI type 128, 16 bytes
OEM-specific Type
Header and Data:
80 10 3B 00 00 5F 46 4A 5F 4F 45 4D 5F 12 00 00
Handle 0x003C, DMI type 128, 8 bytes
OEM-specific Type
Header and Data:
80 08 3C 00 01 03 00 00
Handle 0x003D, DMI type 128, 20 bytes
OEM-specific Type
Header and Data:
80 14 3D 00 03 09 01 01 C0 12 00 01 5E 01 01 01
5F 00 00 10
Handle 0x003E, DMI type 128, 16 bytes
OEM-specific Type
Header and Data:
80 10 3E 00 03 0B 01 01 0A 00 00 00 00 00 00 00
Handle 0x003F, DMI type 128, 16 bytes
OEM-specific Type
Header and Data:
80 10 3F 00 03 0D 01 01 01 02 00 00 00 00 00 00
Strings:
[U:SCB1
[V:CSM1
Useful parameter combinations
Numeric types can be combined using commas.
For example, to inspect the overall memory architecture and all DIMMs:
dmidecode -t 16,17
To inspect firmware information:
dmidecode -t 0,13
This is equivalent to:
dmidecode -t bios
Similarly:
dmidecode -t 1,12,15,23,32
is equivalent to:
dmidecode -t system
The complete mapping of symbolic type names is:
| Keyword | Numeric DMI 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 |
Particularly useful commands
For everyday system administration, only a relatively small subset of the available structures is usually required.
Identify the computer
dmidecode -s system-manufacturer
dmidecode -s system-product-name
dmidecode -s system-serial-number
Check firmware
dmidecode -s bios-vendor
dmidecode -s bios-version
dmidecode -s bios-release-date
Inspect processors
dmidecode -t processor
or just the model:
dmidecode -s processor-version
Inspect installed memory
dmidecode -t 17
Check maximum memory capacity
dmidecode -t 16
Inspect PCI/PCIe slots
dmidecode -t slot
Inspect power supplies
dmidecode -t 39
When dmidecode fails
A typical failure can look like this:
# dmidecode 3.6
/sys/firmware/dmi/tables/smbios_entry_point: Permission denied
Scanning /dev/mem for entry point.
Can't read memory from /dev/mem
There are two separate attempts visible here.
First, dmidecode tried to access the SMBIOS tables through:
/sys/firmware/dmi/tables/
and was denied.
It then attempted its fallback mechanism using:
/dev/mem
which was denied as well.
This is especially common in restricted environments such as containers.
Running:
dmidecode
can solve the problem on a normal Linux installation if it is merely a privilege issue.
Inside an LXC container, however, being root inside the container does not automatically grant access to the host’s firmware tables or physical memory. In such an environment it is normally more appropriate to execute dmidecode directly on the virtualization host.
dmidecode versus /sys
For simple identification strings, calling dmidecode is not always necessary.
On Linux, many of the same values are exposed under:
/sys/devices/virtual/dmi/id/
For example:
cat /sys/devices/virtual/dmi/id/product_name
may provide the same information as:
dmidecode -s system-product-name
Similarly:
cat /sys/devices/virtual/dmi/id/sys_vendor
corresponds roughly to:
dmidecode -s system-manufacturer
The advantage is that many of these sysfs files can be read without root privileges. The dmidecode -t option remains much more useful when complete SMBIOS structures such as memory devices, processors, slots or power supplies have to be inspected.
Summary
dmidecode provides a convenient view into the hardware metadata published by a system’s BIOS or UEFI firmware.
Use:
dmidecode -s KEYWORD
when a single specific property is required, and:
dmidecode -t TYPE
when the complete SMBIOS structure for a hardware category should be examined.
Some of the commands worth remembering are:
dmidecode -s system-product-name
dmidecode -s system-serial-number
dmidecode -s bios-version
dmidecode -t processor
dmidecode -t memory
dmidecode -t 16
dmidecode -t 17
dmidecode -t slot
One important limitation should always be kept in mind: dmidecode decodes information supplied by the system firmware. It does not independently verify that information against the physical hardware, and firmware-provided SMBIOS data can therefore be incomplete or incorrect.
References
The keyword and numeric type lists in this article are based on the dmidecode 3.7 manual from Debian unstable and the SMBIOS/DMI type definitions documented there.