I followed your thread and realize you were having issues with your system restarting by its self.
Here is a list of reasons your computer will restart.
Over heating Processor core - usually caused by faulty cooling fan or clogged heat sink. Or heat sink is not seated properly on top of processor's core.
Corrupted Video drivers or video card failure, sometimes an add-on video card issue can be resolved by cooking the video card in a 300 degree F oven for 10 minutes, this re-flows the solder on faulty connections, any plastic parts and heat sink should be removed from the card before attempting this. This process does NOT work with on-board video processors however!
I think your concentration should be mostly aimed at your processor and if it is being cooled correctly.
You may have a PSU problem as well, your power supply may have failed completely, where as before it was slowly failing to provide a stable supply of current.
At that point using a VOM meter would have showed the voltages as being below normal from time to time.
You can still use a VOM meter to determine if your PSU is still supplying any voltages, or if one rail has failed, or is below spec.
You could substitute your power supply with another one, to determine if your motherboard still boots. If it does, your origional PSU has failed internally.
I would also try disconnecting every plugged in device and plug it back in, sometimes those become loose, or oxidation builds up between the metals on the contacts. This process disturbs the oxidation.
Also with all my advice I must always warn about Static Electricity damage, any time you work on the inside of your computer, I strongly advise you keep one hand on the computers outer metal
casing at all times, and unless you are testing for voltages, unplug the power supply from the wall outlet, to avoid possible short-outs.
Edited by MrBruce1959, 16 April 2010 - 11:06 AM.