About a week ago, I was playing Unreal Tournament on my 64 meg Radeon DDR. The game kept minimizing about every minute, but it ran fine every time I maximized it for about another minute. The next time I booted my computer, it said that a file that my video driver needed to function properly was not there or malfunctioning. Now my computer will only run at 640x480 resolution with 256 colors. I've tried updating the driver, reinstalling it, reinstalling DirectX 8.0a, and reinstalling the GART drivers, but nothing seemed to work.