Solved Semi-frequent lockups win7x64

[Exarkun007]

Hey all, thanks for taking the time to read this!

So I built myself a new gaming rig back in april. Had these same issues I am having now, but they mysteriously stopped, but have now started again. The machine will, seemingly at random, hang and have the spinning blue wheel, at which point I have to hard reset. If I was doing something with sound, like a game or movie, the sound would continue for a while, or loop. It worked flawlessly for about 3 months. Gamed for a few hours, went to bed, woke up and it was off, then it started.

Things I have tried:
Fresh install - Seems to have made them less frequent.
Updated drivers from intel/appropriate manufacturers, to include DX, java, etc - No change
Changed antivirus from AVG to MSE to Avast. - No change
Memtest - Run overnight, no problems
Monitored temps - Everything well in range
Repair install (now running another fresh install) - No change
Event Viewer - Shows nothing other than improper shutdown
sfc /scannow - No errors
Flash SSD firmware - No change
Change monitors to generic PnP panel without drivers - No change
Pull new graphics card, run on HD4000 integrated - Color strobe/cycle after a few minutes.
Disable integrated, run 8800GT I had laying around - Still hangs w/ blue circle, though far less frequently. Can run for several hours before hanging 3-4x as long as with other GPU

Does this pretty much narrow it down to the mobo?

i5 3570k
corsair vengeance (9 9 9 24)
powercolor 7870 ghz edition // 8800gt
ASrock z77 extreme 4 mobo
realtek onboard sound
corsair 600w PSU
after market CPU cooler

Gonna post this before it locks and I can't!

 

[Exarkun007]

Has hung twice since I posted. Moved GPu from pcie 3.0 slot to 2.0 slot, still hangs.

 

[Exarkun007]

New motherboard fixed issues.