I am running XP Pro, IE8 with SP3. This is a new install into a custom built computer. I was having a blue screen problem, and this disappeared, now after I've been using the computer for maybe 1 hr. or 5 hrs., no real pattern, it will freeze and within seconds, the screen goes black. The fans continue to run and I can push the small thin button on top of the handle (not the main power button) and it will reboot and run perfectly. I know this problem has been seen many times, and can be caused by a number of items, one being heat. I've run a heat test, and it appears everything is fine. Anyone who has seen this problem, and can possibly help me, I would greatly appreciate it.