I've had the problem with both ATI and Nvidia cards. There are hundreds, if not thousands that have the same problem i'm having yet it keeps getting ignored. Nothing is ever fixed with the drivers. I had been using 64 bit for a long time and the problem would rear its ugly head after awhile. Sometimes i could get it to go away only to come back again. I finally decided to switch to 32 bit and now its started again after a week. The card i'm using is an X1900XTX if anybody is curious. I bought a 8800GTX awhile back so i wouldnt have this issue. Then to my surprise it did the same thing so i sold the card.