Ive been running tests to find the best settings for Doom 3. Ive got XP Pro and 2000 Pro, clean installs. In 2000 I get an extra 200 points in 3DMark2003(5955) and I can run Doom 3 at Ultra 1152x864 with High Quality Special Effects, shadows and specular off and bump mapping on and I get 45fps. To get those frame rates in XP I had to go down to High Quality 1024. It seems to me that XP should be the better gaming OS???