A couple weeks ago, my system started doing this thing where it won't shutdown, only restart. This all started after I moved it into a new case and it also forgot my BIOS settings a couple of times. It didn't do this restarting this when I built it about a month ago.

Specs:
Asus P5Q Deluxe
Intel Q9450
2 x 2GB Corsair Dominator
ATI 4870
VelociRaptor
Corsair HX620W
Windows Vista Ultimate x64

I've tried different video cards, different PSUs, fresh install of Windows, loading BIOS defaults - nothing changes it. Also in my BIOS settings, all the "wake from ___" options are disabled.