vnf4ultra: What happens if you try opening some moderately-CPU-taxing program like a web browser? See if it changes then.
SpeedStep, as described here, will decrease the CPU multiplier when the CPU is idling (to conserve power). When the CPU starts having to work, the multiplier is put back to normal.
The only thing that's remotely related to speedstep (eist) in my bios is the c1e support, which I disabled, with no effect. This is what I found regarding c1e. http://forums.extremeoverclocking.com/showthread.php?p=2436055
I'm guessing that my bios just isn't up to date enough to properly support the e4300, and they don't have any newer bios than what I have, which is several months old.