Is there some way to tell what is causing my computer to freeze if there's a software conflict? I have formatted/reinstalled all software and it still happens. Sometimes with IE open, sometimes overnight while idling (no programs start overnight), sometimes with only Outlook Express open....I run Qcharts and have some Excel sheets open, but it has frozen with none of these running. I've scanned for virii, searched for trojans with PestPatrol, etc. I built this system in Jan. 2002 and it started a few months ago. Some days it doesn't freeze, and some days it froze 4 times. Ctrl/alt/del does nothing. AMD 1800xp, Abit KG7, Crucial memory, two Seagate Barracuda hds, Windows 2000 Pro with all updates. Also have a Matrox G200, Sound Blaster and a NIC installed. This machine is not overclocked. I'm beginning to think it may be hardware-related, so I may buy another mobo to see if it helps. I'm sure the system has never been too hot...I use MB Monitor. Thanks for any help.