A couple of weeks ago when i started up my computer a red screen came up and it said that my graphics card was not connected. I then exited the screen and loaded up my computer to find that the graphics card had uninstallsed itself. So i reinstalled the drivers and thought that everything would be fine because my desktop had went back to normal. But when i went to load up counter strike, my screen went black and then a sort of multi coloured pattern slowly spread across it. It has done this ever since and i don't know what to do to fix it, please help!
My gfx card is a radeon x800 256 mb.