How to identify a device > RAM
How to identify the installed Memory / RAM.
Many people simply use free, which is available on every Debian system, to list the quantity of RAM installed (detected). Gnome users can install and use the hardinfo. KDE user can use kinfocenter.
free
free is the Unix command to know about free/used/available memory on your system:
$free
total used free shared buffers cached
Mem: 2067696 790564 1277132 0 119108 184924
-/+ buffers/cache: 486532 1581164
Swap: 998572 316908 681664
under Gnome: hardinfo
Gnomes's System Information (Hardinfo in Menu Applications/System Tools, from package:hardinfo) has an information page on the RAM installed.
under KDE: KInfocenter
KDE's KInfoCenter (in K Menu / System / KInfoCenter Info Center, from package:kcontrol) has an information page on the RAM installed.
dmidecode
dmidecode can be used to query the motherboards DMI zone about RAM, Ram Slot(s) and Memory Controller:
dmidecode -t memory is equivalent to running the 4 commands below (i.e dmidecode -t 5 -t 6 -t 16 -t 17)
Memory Device
$dmidecode -t 17
# dmidecode 2.9
SMBIOS 2.4 present.
Handle 0x002A, DMI type 17, 27 bytes
Memory Device
Array Handle: 0x0029
Error Information Handle: No Error
Total Width: 64 bits
Data Width: 64 bits
Size: 1024 MB
Form Factor: SODIMM
Set: None
Locator: DIMM 1
Bank Locator: Bank 0/1
Type: DDR2
Type Detail: Synchronous
Speed: Unknown
Manufacturer: Not Specified
Serial Number: Not Specified
Asset Tag: Not Specified
Part Number: Not Specified
Handle 0x002B, DMI type 17, 27 bytes
Memory Device
Array Handle: 0x0029
Error Information Handle: No Error
Total Width: 64 bits
Data Width: 64 bits
Size: 1024 MB
Form Factor: SODIMM
Set: None
Locator: DIMM 2
Bank Locator: Bank 2/3
Type: DDR2
Type Detail: Synchronous
Speed: Unknown
Manufacturer: Not Specified
Serial Number: Not Specified
Asset Tag: Not Specified
Part Number: Not Specified
Memory Controller Information
$dmidecode -t 5
Handle 0x0007, DMI type 5, 20 bytes
Memory Controller Information
Error Detecting Method: None
Error Correcting Capabilities:
None
Supported Interleave: One-way Interleave
Current Interleave: One-way Interleave
Maximum Memory Module Size: 2048 MB
Maximum Total Memory Size: 4096 MB
Supported Speeds:
Other
Supported Memory Types:
DIMM
SDRAM
Memory Module Voltage: 2.9 V
Associated Memory Slots: 2
0x0008
0x0009
Enabled Error Correcting Capabilities:
Unknown
Memory Module Information
$dmidecode -t 6
# dmidecode 2.9
SMBIOS 2.4 present.
Handle 0x0008, DMI type 6, 12 bytes
Memory Module Information
Socket Designation: DIMM Slot 1
Bank Connections: 0 3
Current Speed: Unknown
Type: DIMM SDRAM
Installed Size: 1024 MB (Double-bank Connection)
Enabled Size: 1024 MB (Double-bank Connection)
Error Status: OK
Handle 0x0#009, DMI type 6, 12 bytes
Memory Module Information
Socket Designation: DIMM Slot 2
Bank Connections: 4 7
Current Speed: Unknown
Type: DIMM SDRAM
Installed Size: 1024 MB (Double-bank Connection)
Enabled Size: 1024 MB (Double-bank Connection)
Error Status: OK
lshw
You can also check information about RAM (like speed, type, etc) using lshw (from package lshw).
$ sudo lshw -short -C memory H/W path Device Class Description ======================================================= /0/0 memory 1MiB BIOS /0/19 memory 4GiB System Memory /0/19/0 memory 4GiB SODIMM DDR3 Synchronous 1333 MH /0/19/1 memory DIMM [empty] /0/19/2 memory DIMM [empty] /0/19/3 memory DIMM [empty] /0/27/29 memory 32KiB L1 cache /0/27/2a memory 256KiB L2 cache /0/27/2b memory 3MiB L3 cache /0/28 memory 32KiB L1 cache
References
manpages: free(1), dmidecode(8)