I really wouldn't buy either because of the costs, but if pressed I'd go with the 6800GT. The games I play are mainly OpenGL based, and in that scenario its no contest. Plus, Nvidia has good support with Linux, which I swtich to when I'm not playing games. Although the 2 slot 6800U is faster, I don't like the idea of using 2 slots and 2 molex. I have a 9800Pro and ti4200 now, and to be honest I don't see that much difference in image quality, so aside from knowing that its faster, it wouldn't justify a purchase of the x800 series because of the OpenGL performance. Looking towards Doom3, it would seem that the 6800 series will be a better card. Who knows when HL2 will come out...for me thats in the Duke Nukem Forever category. Even in DirectX games, the performance seems about the same between the cards. I don't know what the point of running 1600x1200 4AA/8AF would be, since the 1600x1200 resolution makes anti aliasing somewhat mute.