I have come to the conclusion that the new ATI Radeon Official XP drivers are a complete piece of crap. OpenGL never ran so bad, CS ran very choppy. And so I switched back to Win2k Alternate Display Driver on ATI.com's drivers page (which even though are not MS WHQL certified run great in XP with no problems). These drivers are awesome and OpenGL now runs top notch. So I recommend to anyone who is into gaming, wants the performance and uses XP to use them
That is until ATI comes out with an updated XP driver.