PC Completely freezes shortly after boot

[imnewheredontkillme]

I was having some issues with an overclock I had a few days ago causing poor performance in games. I returned the CPU to stock clocks and voltages, the issues were resolved meaning my overclock became unstable over time. Since then I've had no issues till now. My PC began freezing, it gets completely locked up and I have to force shut it down. In the short time I have till it inevitably locks up, I checked core temp, and the windows performance monitor. Everything checked out, no CPU maxing out or overheating. A long with normal ram use and disk use. I'm completely confused on what's happening, I'm on the latest drivers for my gpu so i don't think that's the issue. If anyone can point me in the right direction that'd be great.

[pentotark]

If temperatures are fine, before calling out the CPU you might want to check no overclock or xmp is applied to your RAM and if you happen to have 2 or more modules attached, try one at a time. Faulty modules could lead to sudden crashes. Hope this helps.