GA-8N-SLI loosing display on restart after RMA

I just got my Gigabyte GA-8N-SLI mobo back from Gigabyte RMA to get two burnt capacitors replaced. The job was done under warranty (and THREE F'n weeks!!!) and at first things seemed to be ok. Before the repair, the machine would freeze after 3-5 min. operation, and wouldn't restart until allowed to cool off.

After the repair, the machine starts ok from cold, but on a restart the machine doesn't see the graphics card in the PCI-E slot (or perhaps just doesn't see the PCI-E slot itself) and give the beeeeeep of a hardware prob. Then it seems to go ahead and boot, and continues to run, sans graphics. If allowed to cool off for several minutes it will start normally (so far) and will run (so far) with no problems (yet).

Has anyone ever encountered this sort of thing? I don't want to get my ATI Radeon X1950 cooked, and I don't want to have to go through the Gigabyte RMA thing again.