Ok, I had this issue with my Q6600 and MSI P6N-FI motherboard. Spent a week trying to Overclock the CPU to 3.0GHz and to no avail I had the CPU at 1.5 volts and It was not stable for more then an hour. Then I saw the VTT voltage and increased it 12% and lowered the CPU Voltage down to 1.28 and my system has been stable. Ran 4 instances of Prime95(one in blend mode) for 8 hours. Did Memtest86+ for 2 hours and the memory checked out. My question is, could my previous overclocking/overvolting of affected the cpu to the point that game graphics are corrupt. In UT3 the characters' polygons blink in and out of existence and in Crysis I see white dots around the Icons for picking your suits power. Popped in my 7600gs and still had graphical issue, so it's not my 8800GTS. I popped in my E4400 and checked it at stock and OC, and both had the same issue. Could both CPU's be bad? Uninstalled and reinstalled the nVidia drivers and still corrupted. Uninstalled and reinstalled UT3 and I still get the same Graphic corruption. Could the motherboard be borked? Or did the OC just corrupt those games? Then again HL2 has very slight graphic corruption in some parts, but nowhere near as noticible as the other two games. Any assistance would be appreciated.

I doubt that simply increasing the voltage like that would bork a CPU. Did you clean the drivers out with drivercleaner first? Also, check your PCI-E frequency and make sure it's locked at 100mhz.

Yes and especially if the E4400 gives the same result when running standard and overclocked. What about the GPU temps?

I believe it is locked at 100mhz, but the bios wont let me lower it to compensate for the higher fsb. I also decided to fire up a game that I didn't try during my original ordeal, Call of Duty 4. Looked really hard to find any anomolies, but not appeared, it was as solid as it has always been. It might be the installs...but it it were UT3 would be fine cuz I uninstalled and reinstalled that game!!! Argh....I don't wanna have to reinstall windows!