Possible Duplicate:
Windows 7 Freezes (No BSOD)
Recently when I have been playing or using relatively graphics intensive things like bad company 2, unreal development kit(test/run mode), or crysis2, windows will lock up during gameplay even though task manager is reporting average amounts of use. when it locks up I am unable to do anything and I end up having to force shut down. The first time this happened it was about thirty minutes in and each time since it has happened quicker. I am running windows 7 ultimate x64 on a 3 year old modified hp desktop. Every component seems to be working fine except for one fan that will occasionally make some noise. What could be causing these crashes/lockups?
