Zimbardo said:
i'd say Intel Burn Test is the best way to test the stability of your overclock. do about 10 to 15 runs at max memory, and if you're stable, you should be good to go for a nice round of Prime95.
My test suite for OC stability has been as follows for some years now:
(1) 24 hours of Prime95. Yes,
24 hours. If you're not 24 hours Prime stable, you're not REALLY stable!
(2) 24 hours of memtest86+
(3) 4 hours of looping 3DMark, any version you like
Recently I've also added 15 minutes of IntelBurnTest as a quick OC test too. If it survives 15 minutes of IBT I feel reasonably confident about doing the 24 hours of Prime95, reducing wasted time. I also like to use the eVGA OC Scanner's built-in artifact tester for about 15-30 minutes to make sure the videocard isn't having minor artifacting that I can't see with my eyes, because you can still kill a videocard slowly if you let it artifact on you even if you can't see it happening. Uh, you'll need at least one eVGA videocard in your machine for that. Otherwise you're SOL. :3
About Prime95: I set the Priority of Prime95 to 9 when I do the 24 hours run. If you set it to 10, you essentially lose the ability to control Windows since 10 is higher than everything but the kernel. At 9 I can also look at Real Temp or CoreTemp and it will update properly, at 10 both monitoring utilities lock up and won't work.
Yes, I have extremely demanding OC stability testing. However in my experience any machine which passes this suite has never crashed on me, even when running games that make other people's stock-clocked computers crash. I therefore generally regard it as authoritative, I can say with 99.99% accuracy that if your machine can survive my testing suite, your OC is stable for 24/7 everyday continuous use.