Muchas gracias a todos por responder.
He estado indagando con comandos en linux y he descubierto que tengo otro slot libre, pero me sale como máxima memoria 4GB.
root@manutepowa-X550DP:/home/manutepowa# dmidecode --type memory
# dmidecode 2.12
# SMBIOS entry point at 0x7ee36a98
SMBIOS 2.7 present.
Handle 0x0022, DMI type 16, 23 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
Handle 0x0024, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x0022
Error Information Handle: Not Provided
Total Width: Unknown
Data Width: 64 bits
Size: No Module Installed
Form Factor: Unknown
Set: None
Locator: A1_DIMM0
Bank Locator: A1_BANK0
Type: Unknown
Type Detail: None
Speed: Unknown
Manufacturer: A1_Manufacturer0
Serial Number: A1_SerNum0
Asset Tag: A1_AssetTagNum0
Part Number: Array1_PartNumber0
Rank: Unknown
Configured Clock Speed: Unknown
Handle 0x0026, DMI type 17, 34 bytes
Memory Device
Array Handle: 0x0022
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 4096 MB
Form Factor: SODIMM
Set: None
Locator: A1_DIMM1
Bank Locator: A1_BANK1
Type: DDR3
Type Detail: Synchronous Unbuffered (Unregistered)
Speed: 1600 MHz
Manufacturer: Samsung
Serial Number: E14FA99F
Asset Tag: A1_AssetTagNum1
Part Number: M471B5173QH0-YK0
Rank: 1
Configured Clock Speed: 1600 MHz
Lo llevare para que me prueben un modulo haber si lo permite.
Gracias a todos. Saludos