This guys AMD64 system with the 9600XT barely runs the same settings better than my computer...which doom defaults the settings to high quality 800x600 resolution, no aa, no af, but all effects. It just barely gets smoother framerate than my FX 5700 and that's not even if I OC'd my 5700. My computer runs it up in the 40's usually and will dip into 20's or 15 or so during a really heavy part, but mostly it's playable and not laggy enough to bother me.