Computer freezes, completely unresponsive

This has been a problem for about a week or so. The computer freezes and wont respond to any keyboard commands (NUM Lock light stays on when pressing the key, and the mouse light turns off after a few seconds.) It seems to happen fairly randomly.

I have XP and Vista Ultimate in a dual boot configuration and it seems to happen more in Vista than XP. Once it froze when I right clicked the desktop and clicked the NVidia control panel in Vista and another time it froze when viewing various picture files in Vista as well. Im using the AERO theme in Vista and the classic theme in XP.

I did a few stability tests and it never froze so I dont think its overheating.

My specs:
CPU: AMD X2 3000+
Mobo: M2N32 SLI Deluxe Wireless Edition
GPU: eVGA 7600GT
PSU: Thermaltake 700W

 

It could be your memory. Get mem test and scan it.

 

I'd recommend running an extended hard drive diagnostic also. You download it for free from your hard drive manufacturer's web site.

 

I did a memory test and hard drive diagnostic and everything appears normal. I defragmented the drive, disabled a wireless card that can cause problems sometimes, and updated the GPU driver for Vista and I still have the same problem.

It only happens when I am actually using the computer. If I leave it on all day and don't touch it, nothing goes wrong. One day it froze when I was browsing through my pictures and so I decided to bring up the Windows picture viewer thingy and click the 'Next' button as fast as I could to see if it would freeze and it did.

I use Guitar Pro 5 a lot and play along with the MIDI songs. It never freezes while doing that. It seems it only freezes when I am actively clicking on things.

 

I just thought of something. A while back I was playing the C&C 3 Demo and my video card (eVGA 7600GT) must have overheated or something because the VGA output has weird colors and lines on white backgrounds, so I have to use the DVI out now. Since my video card is messed up, and it seems my pictures freeze up while clicking through them very quickly and clicking the NVIDIA control panel froze it, could it be that my video card is causing the problem? Is there any way to test it to make sure?

 

3DMark should be a good video card test. http://www.majorgeeks.com/download.php?det=4936 Run the test several times in a row.

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