it is odd, my AMD 3200+ Barton and BFG 6600GT played Doom3 perfectly fine. I'm hoping it will work as well for Quake 4 also.

A friend of mine has this problem with a similar system. What he has found is that some of the capacitors on his MB are going bad. This has caused problems wit h is Nvidia vid card causing much lower FPS in games then he has enjoyed in the past.