Re: GTX 295 problem.
I have a new Zotac GTX 295 and noticed screen flickering in the games I was trying. On GIRD, screen flickering went away when I enabled Vsync in the game. I haven't gotten around to confirming if that's going to resolve it on the other games once I enable Vsync in the global drivers.
Figure I might as well have it on since my LCD has a standard 60hz refresh.
(edit) Vsynch seems to have fixed all my glitching. Hope that works for you!