I just noticed today that my trusty 3,1 is not recognizing the RAM loaded on Riser B. In System Information, it shows Riser A full with 8GB, but Riser B shows as empty. Here's the configuration of my 14GB RAM: Riser A: 2GB | 2GB | 2GB | 2GB Riser B: 1GB | 1GB | 2GB | 2GB I've pulled Riser B, inspected and cleaned and re-seated the RAM and placed the riser back in the slot nice and tight, but it's still not showing up in System Info. Like I said, I just noticed this today, so I don't know how long this has been going on. I'll try switching some of the RAM sticks to determine if they are dead or if the culprit is Riser B (which I suspect). Anyone have any other ideas?