Покажи dmidecode -t memory и grep mem /boot/grub/grub*.
dmidecode 3.3
Getting SMBIOS data from sysfs.
SMBIOS 2.7 present.
Handle 0x0008, DMI type 16, 23 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: None
Maximum Capacity: 8 GB
Error Information Handle: Not Provided
Number Of Devices: 2
Handle 0x000A, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x0008
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 4 GB
Form Factor: DIMM
Set: None
Locator: A1_DIMM0
Bank Locator: A1_BANK0
Type: DDR3
Type Detail: Synchronous
Speed: 1600 MT/s
Manufacturer: Undefined
Serial Number: 00000000
Asset Tag: A1_AssetTagNum0
Part Number: CT51264BA160B.C16F
Rank: 2
Configured Memory Speed: 533 MT/s
Handle 0x000C, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x0008
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 4 GB
Form Factor: DIMM
Set: None
Locator: A1_DIMM1
Bank Locator: A1_BANK1
Type: DDR3
Type Detail: Synchronous
Speed: 1333 MT/s
Manufacturer: Undefined
Serial Number: 00000000
Asset Tag: A1_AssetTagNum1
Part Number: AE34G1339U2
Rank: 2
Configured Memory Speed: 533 MT/s