I've been trying to figure out a problem for the last year, and only recently have I got a clue where the problem is starting from. My parents bought a very new fast pc last year, and I installed XP on it. Occasionally the system would freeze up, and the people at the store I bought it at treated me like a newbie explaining that computers sometimes freeze. I had to set them straight and let them know that I am a developer, and I know what I'm doing, but this freezing was unacceptable. I was able to always re-produce the problem by playing Unreal Tournament, but other Graphic intensive games didn't always freeze. The System Process would go to 99% and not let any other processes work whenever this freeze happened. I brought in the pc to where I bought it thinking it was a hardware issue. They were unable to reproduce the problem, and so told me they had done everything they could. I eventually tried just unplugging different devices seeing if that would get it to stop freezing. I eventually saw why they didn't have any problems, they were not plugging in any USB devices when they did the testing. I found this thread by looking for a device driver to replace my current driver "Sis 7001 PCI to USB Open Host Controller", and thought I might suggest, unplug all USB devices then try to play the games. If it doesn't crash, then you have the same problem as me, and at least I'm not alone. Hopefully someone else reading this knows of the way to fix this problem without running the pc with no USB devices. My parents would like to hook there printer back up full time, instead of just plugging it in when they need it. Any help anyone can give to this would be most appreciated.