sudo dmidecode -t memory
# dmidecode 3.0Getting SMBIOS data from sysfs.SMBIOS 2.4 present.Handle 0x0020, DMI type 16, 15 bytesPhysical 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: 2Handle 0x0022, DMI type 17, 27 bytesMemory Device Array Handle: 0x0020 Error Information Handle: Not Provided Total Width: 64 bits Data Width: 64 bits Size: 2048 MB Form Factor: DIMM Set: None Locator: J6H1 Bank Locator: CHAN A DIMM 0 Type: DDR Type Detail: Synchronous Speed: 667 MHz Manufacturer: Unknown Serial Number: Unknown Asset Tag: Unknown Part Number: UnknownHandle 0x0024, DMI type 17, 27 bytesMemory Device Array Handle: 0x0020 Error Information Handle: Not Provided Total Width: 64 bits Data Width: 64 bits Size: 1024 MB Form Factor: DIMM Set: None Locator: J6H2 Bank Locator: CHAN A DIMM 1 Type: DDR Type Detail: Synchronous Speed: 667 MHz Manufacturer: Unknown Serial Number: Unknown Asset Tag: Unknown Part Number: Unknown