Well the guy is in the same sort of boat as me, he can't get above 3.2ghz with his e6600. I had 3.4ghz for a while (377 x 9), but found I got better results generally with 400 x 8 (3.2ghz), I think this is due to the memory running at default rather than underclocking. Like me, hes tried upping the cpu volts, MCH, FSB, and nothing seems to get him, or me for that matter, any higher. Both are temps under load are fine, mine 53c load and his is 55c load, so its not that. I've tried running at 415fsb with 8 multi but that means the ram runs above default and it doesn't like that either.
Seems to me that 400 x 8 or 355 x 9 is about the most he or I can get. Really don't know what to do for meself or suggesst for him to try.