I just OC'd my Opty 165 recently. I've tested it stable with Orthos Prime for 8 hours, and it seems stable. However, today while running several different programs, including folding@home my computer shut off completely. It did start right back up after 30 seconds by using the power button. Then a couple of hours later, I ran OCCT and folding@home at the same time. After OCCT completed its first minute of monitoring and started to load the CPU, immediately shut down again. It again turned right back on without any problem, and has been fine ever since (but I have not loaded the system heavy since the last shutdown). Could this be an undervoltage issue? It is currently at 2.67 Ghz at 1.4v. I do NOT think it's a power supply issue, as I'm running a Corsair HX620, only have one video card, and 2 HD's. Also, my temps are good 30 idle and 46 at full load (according to Smartguardian. Any ideas??