I have an XFX 6800XT card
that is quite unstable under Vista RTM using NVidia's RC2 drivers. I run at 1600×1200, and I will lose video on one or both monitors quite reliably if I try to watch a video file using WMP, and often when I look at still pictures as well. Often I will get video back, and Vista will give me a taskbar balloon saying that my "video adapter stopped responding and has recovered."
Reading the forums here, my experience seems to be worse than average; most RTMers like me seem to be reporting solid 2D performance and problems when they try to play 3D games. I was wondering if anyone would point out why I might be having an especially bad experience, and if I should update to some of the unofficial drivers that are being discussed.