Ok. I have another (bad) idea. I looked up your other posts and you mentioned this started happening after you bought a new graphics card. My computer was acting up, also right after installing a new graphics card. My problems were completely different from yours (black screen right after windows logo on boot up, monitor would shut off along with all peripherals). To this day I still don't know what caused it, but it stopped happening after I reset the CMOS. This will reset all of your BIOS settings including overclocks, and I think fan profiles. Your problem really sounds similar to mine in many aspects so if this doesn't fix it, I don't know what will.
Edit: to reset CMOS power down, turn off PSU, unplug power supply, hold down power button to drain any remaining electricity left in the components, locate the silver (usually), round, battery thing that looks like the one that goes in watches, take it out, leave it aside for 30 seconds (15 is enough, just to be safe 30 seconds), put it back in and power on.
Edited by TheMasterNoob - 8/21/13 at 11:11am