Maybe check if it really is a Ram issue. by Removing the Ram stick. then you should get a error for NO ram found.
Ram does go bad, but then it is mostly the SMD capacitors or resistors on the PCB.
Or the chips have to be Reflowed due some of the solder balls being broken off.
Resulting in 1 of the Pins of the chips not working as intended. {if it is a ground pin it is no issue, but if it is a data pin, it is a issue}