I may add that I clocked mine (x2 3800+ for s939) to 2.4 GHz without breaking a sweat, and it wouldn't heat up (ok, I'm not using the standard cooler, but the one I use is geared towards silence not high temp cooling)
More than likely, you've hit a snag concerning your RAM: reset the RAM settings to auto and try again.
Clean up your CMOS and do a proper attempt.
If you're using a mobo that scales the RAM's speed up when you clock the CPU higher, try to underclock the ram.