I recently got a BFG 6600gt (agp). So far it seems like a pretty good card, especially for the money. But I'm having some problems with it. When playing HL2 for a bit, I get a lot of flickering, artifacts, tearing, weird colors, etc. Even in Windows graphically things seem a bit sluggish. Like clicking on a drop down menu, it'll take a couple seconds for it to pop up. Especially going into display properties and clicking the advanced button. My cursor will freeze up for a few seconds. As it will when I click on the Nvidia tab. Around the net I've read a lot of people having problems with these cards, though it seems to be more related to drivers than anything. What drivers are people having good luck with? So far I've tried 66.93 from Nvidia's site. From guru3d.com I've tried 71.20, 71.40 and 71.80. 71.80 was the worst in games. On top of the other things it would also stutter. I've also been using a couple different driver removers in between. Temp never goes above 50C.
I don't think it's my computer, my previous card I never had these issues in Windows I see now. Though I couldn't use the previous card to game so. My system is:
Iwill DK8N (nforce3 chipset)
2x 244 Opterons
4x 512mb Corsair 3200LL-RE
System/apps drive is 36gb Raptor
Antec 550w EPS PSU
I'm running an XFX 6600GT PCI-E w/no problems using the 66.93 drivers off nvidia.com. Your system, judging by the specs you list, should no issues at all with HL2. When you upgraded video cards, did you just swap one out for the other? Personally, when I upgrade a video card I normally just go ahead and reformat/reinstall Windows (good practice anyway to do so every 6 to 12 months). It's a pain in the arse to completely wipe your computer of old drivers for cards no longer in the system.
In just two days, tomorrow will be yesterday.