I'd suspect heat as being the problem. Short term intermittent crashes usually mean your CPU is over heating. Are the fans running when this happens? You might wish to down load this software to get an indication of your systems operating temperatures:
http://www.almico.com/sfdownload.php
Can you provide more detailed information concerning your graphics card/chip set this information can be found in device manager. start> control panel> administrative tools> computer management> device manager> click on display adapter. Write down the information provided and post it here. Also provide your OS information (example: XP Professional SP2, etc.).
I'm running an HP Pavilion Media Center m470n purchased about 3 years ago. I've experienced some "lock-ups" when looking at Google-Earth and occassionally the TV Media Center view will cause a lock-up, other than that most things seem to function fairly well. I don't do gaming, but my son has mentioned some lock-up on occasion with some game stuff. This causes me to wonder if a graphics card upgrade wouldn't be adviseable. The present graphics card info shows Radeon 9200, and also a "secondary" when I look at the advanced systems information. Apparently there is a vacant PCI slot available. I've never upgraded graphics cards - memory yes, but not graphics. I have used "video capture" from analog on occassion and want to be able to continue that with any upgrade I might do. I'd like your recommendations, if you have any? Thanks!

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