OcUK 'Pre-overclocked' CPU questions

[OrphanBoy]

Hiya,

I'm sure this has been asked before but searching on here for 'overclocked' wasn't going to yield good results
Anyway, what's the score with the pre-overclocked CPUs available on the OcUK store? Intel's not gonna put stickers on the good ones saying which can pull what, as that wouldn't make them extra money!

So how does OcUK figure out which ones are good or not? Do they go through box after box of CPUs testing them? What happens to the ones that don't clock well? Do they go back into their retail boxes to be sold normally? Does this mean that if I buy a Q6600 from the store that's not pre-overclocked that it'll be a dud as someone's already deduced this?

Ta guys

 

[OrphanBoy]

Ah right, cool. So do you just return it in the included envelope in exchange for a new one or something if it doesn't get to the rated clock speed?
Out of interest, how many do get returned that don't make the given clock speed?