Okay i recently tweaked my C2D and added my H2O loop back in, and started the Overclocking. This is when i found out that my Northbridge on my ASUS p5n32-e gets a little too toasty... Thanks to receiving a DMM in the mail i stuck the temp probe on the top of the heatsink and it was pushing 70-75C and it runs nearly 70C at stock speeds and voltage.

I know that the board relies on the cpu HSF to spread air around, however i didn't think it would be a problem switching to H2O since i have a 120MM fan blowing directly onto the NB heatsink.

At first it would just randomly lock up once it hit about 77C. I reset everything to stock and was about to order a waterblock for the NB to cool it down a bit. However i am not sure that's the problem. Now two full weeks later and a fresh OS install (I thought with the abrupt restarts and OCing it would be best just to make sure it wasn't a Windows issue) its still restarting randomly.

Just to be sure i double checked my PSU its a Antec Neo 550W the 12V rails and the 5V rails seem to be fine? All the PSU calculators i have used say i only need a 400W PSU with all my goodies. Other than that everything seems fine?

So who would say its a mobo issue?

I would first off run a stress test with EVERYTHING at stock - I use everest ultimate , orthos, and there are others out there too.

After that if it locks up / crashes , try swapping out the psu if possible to a more powerful one , just for giggles.

If it still locks up , try running seperate tests on memory , video, cpu , disks ( everest has options for most of these )

if you get lock ups during every seperate test , then yes i'd kinda suspect the board of borking up just because ALL your parts cant be bad

Make sure everything is seated , plugged , connected etc just in case you overlooked something.

last but not least - I'd recommend doing ALL this on a bench / box / bag ( GETTO TEST!! )