It works on its own but fails when connected together.
It works on its own but fails when connected together.
It's strange if RAM fails while everything else seems fine. The CPU memory controller might be affected, but that seems improbable unless the board is faulty. Damaged traces are possible, though rare—bad boards usually fail completely or lose a channel. A corrupt BIOS could cause issues, but since nothing was changed, it's unclear why suddenly it happened. I've noticed mounts shifting and pins not connecting properly, but memory errors haven't been seen before.