The way I go about ensuring stability is that I make sure my rig is prime and linpack stable (even if it's just a few minutes) at a minimum 200 MHz above my target 24/7 overclock with the same voltage settings.

I run my rig @ 100% cpu for 24/7.

Current 24/7 setting: 3.5 GHz (167 x 21), 1.15 vcore, 1.2 uncore.

It is prime and linpack stable @ 3.8 GHz (181 x 21), same voltage settings.
20 days straight of 24/7 100% cpu... no problems.


Similarly, my alternate 24/7 settings is:
3.8 GHz (181 x 21), 1.25 vcore, 1.275 uncore.
But it is prime and linpack stable @ 4.0 GHz (191 x 21), same voltage settings.
I'm currently running this setting (@ 3.8 GHz) 24/7. To test it out for a few weeks.


I think this is how Intel bins them, but they do it with a much larger safety buffer. (probably on the order of 1 GHz for the 920s and 800 MHz for the 975s...)



Of course, any sort of safety buffer (even if it's just 200 MHz) is unacceptable to most OC'ers even for 24/7 . But for me, I prefer the reliability. Since I run @ 100% cpu 24/7.

*On the other hand, my benchmark settings have no safety buffer...