Pentium D 965 XE - BlueScreen non-Overclocking

Ok,

I have an ASUS board, I recently upgraded from Pentium D 840 3.2Ghz to a Pentium D 965 Extreme Edition. It is booting up to Windows just fine. Ever since, i got a few blue screens and randomly freezes. I've run MemTest86 and Prime95_x64 for hours and things are fine. I'm running Vista x64 by the way. It stood me up once when i was try to re-organize the Quick Icons by the start button. Other times i was browsing my HDD and i got a blue screen.

I'm confident there is nothing with RAM, As soon as I downloaded "Hot CPU Tester Lite Edition", Unchecked everything and started testing one thing a time. Tested "Memory" for 30mins with no issue. MMX for 7mins and it went dead/hanging. Reboot and run the test again with no success with each option individually nor all functions available in Lite Edition at once.

What might be wrong, is it possible the Used Pentium D 965 XE I recently got is defective? But the test was fine with Prime95

Everything in BIOS is left as default, not Overclocking yet. VCore is read as 1.26v in CPUZ, vCore idle 27c, 38c with Prime95, 35 with Hot CPU Tester while it running for that first 4-7mins before it freezes.

I thought there wasn't enough voltage so i cranked it to 1.30v upto 1.35 but it doesn't help.

Any input would be much appreciated.