I'm guessing that the motherboard is the carrier of the disease..It may be the originator of the problems. Try replacing it.
Hope this helps.
My PC I built is having some early issues. First I had a stick of memory go bad on me. Then my 450W power supply overheated and was literally smoking. I got new memory and a 500W power supply and my PC will only start for a few seconds before shutting itself off. I'm not sure if my 500W power supply is the problem, the new memory, or another issue like my processor is overheating or bad motherboard. Any ideas would help! Thanks!