the 4.2GHz it super cherry picked chips
ones with low stock voltages that overclock better than the majority - we get very few of these
that is why the price is significantly more
each bundle is stressed at the higher clock to make sure it is capable
due to the way in which the bundles are produced by myself, each bundle is speedbinned and assigned to a customer dependant on what speed they have ordered
the fenrir is a good cooler and can handle 4GHz
but it is essentially a value heatsink
the 4.2ghz bundles are set to have megahalems attatched
i have tested 4.4GHz on LinX using this cooler and it is more than up to the job
I got the 4Ghz bundle with the Fenrir (now replaced with a corsair H50) and can hit 4.2Ghz no probs. By the way my 4ghz Bundle came as stock with no AS5 or bios profiles and still no reply from support even tho they promised to send me the profiles and TIM.......
Anyway, overclocked it myself in the end and must say buy the 4ghz OC and take the chance.
http://i558.photobucket.com/albums/ss22/gaidin109/42OC.jpg
http://i558.photobucket.com/albums/ss22/gaidin109/421600intelburntest.jpg