During usage, my computer will freeze. Sometimes during a game like the Sims and sometimes while just surfing the net. When it freezes, a horrible sound comes through the speakers. It will not let anything happen... no mouse movements nor key stroke operations - Ctrl+Alt_Delete does not work. I have run a system diagnostic test with Norton and it shows that there is nothing wrong. I also downloaded TuneUp Utilities 2003 from CNET and it shows nothing being wrong. I've defragged and I have plenty of space on the hard drive. I also let the system manage the Virtual Memory. I have a GForce3 64MB video card. Any ideas what mihgt be wrong?

Are you by any chance using zone alarm firewall? Reason I ask that is norton and zone alarm do not get along ...I used to run norton av and zone alarm...when there was conflict I would freeze up and get a fairly loud kinda grinding humming noise....took off norton av , installed mcafee and had no problems since....when my ctrl+alt+del did work it was vsmon that hung which is part of zone alarm Dont know if it's what is wrong with your puter but just a thought.