The title only allows me so much to work with, so I'll clarify here: After overclocking my system to a stable 2.8 Ghz (400x7), I'll run all the tests to make sure that it can handle it.. then when I shut it down for the night and power it back up the next morning, it will not POST. I have to manually reset the CMOS using the 2-pin jumper on the motherboard. Here are as many specs as I can possibly imagine needed: MB: Gigabyte GA-965P-DS3 (revision 1) BIOS: F14 (Latest that I know of) Processor: Intel Core 2 Duo E6400 RAM: 4 GB Kingston PC2-6400 (2x2GB sticks) RAM Frequency: 800 (2:2) CPU Bus speed: 400 (100-700 is range, iirc) Multi: x7 (6-8 is range) GPU: PowerColor ATI Radeon 4870 512 MB (Stock) Vcore: 1.25v (normal is 1.325v) All other volts: Normal PSU: Corsair VX550w (fairly new, few months out of the box.. readings seem fine on multimeter) Case: CM Storm Sniper Extras: Sound Blaster Audigy, USB External Maxtor HDD (500GB), Canon 3:1 Printer, Copier/Scanner, Fax Machine CPU Cooler: Cooler Master Hyper TX2 I've poured over as much documentation as I can find, considering the case is tough to google out. Many things point to disabling the Legacy USB Storage support on the BIOS, as that can tend to mess with your settings when booting up. I did that, no help (I even unplugged it altogether). It's hard for me to justify changing any of the OC settings, considering it runs stable through OCCT and p95 without an issue. The reason why I dropped the voltage so much, is because it runs fairly hot with it so high.. and I don't see a reason why it needs to be up there, considering how stable it runs where it's at. I've played with trying to get 3.0 Ghz, but that's another issue altogether. I'm content with 2.8, but I'm baffled as to why it's not holding it. A reboot is fine.. even 30 minutes of chill time. But longer than that and it just won't POST. What am I missing?