So I had my rig all set up, i7 3930K, Rampage IV Extreme, 16 gb of ram, two Nvidia 680GTX's. I had a stable OC at 4.325Ghz with my vcore (manually locked) at 1.400V, then once a couple weeks back I left my computer folding while I went off to work, came home and found it off, went into BIOS and saw vcore at something like 0.900v or 0.750v. After manualy setting the vcore back to 1.400V it was working great. Now twice in one day the computer has completely frozen up and when I restart both times I find vcore at 0.934v (or right in there, both times it was different but it definitely was in the 0.9..'s). Any idea what could be causing this? Dying mobo?