Posted 11 March 2010 - 07:29 AM
I tend to lean towards hardware concerns with "hard" restarts. HD video decoding puts a lot of strain on that CPU (I assume onboard video).
On a system of that vintage I would suggest pulling the side panel and see how much dust/trash has accumulated in the heatsinks and clean accordingly. Check to make sure the fans are spinning. Look around for bulged/leaking capacitors while you are in there. You might pull out a stick of memory,or swap memory around, to see if that has an effect. Try running one stick at a time to see if anything changes.
Check voltages. No idea on the quality of that PSU. Easiest way is to get a cheap multimeter/DVOM and check voltages. Look for a spare/unused molex(4 pin) connector and check. 12V+ is the yellow, 5V+ is the red, both blacks are grounds. Keep the meter hooked up when stressing the CPU to see if voltage on the line drops out of spec.
Those are the easiest things (hardware) to check. As far as a software problem, did you change/install any new programs about the same time your problems syarted?
I am a retired Ford tech. Next to Fords, any computer is a piece of cake. (The cake, its not a lie)
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