Quote Originally Posted by BLunTSmoKeR View Post
Disabling C1e and EIST in Advanced CPU Features will prevent the multi from dropping.

I personally prefer to leave these settings enabled in the BIOS, as it saves energy, and as far as my experience goes, they don't have any effect on stability.
It can have a big effect as it may throttle back the CPU and undervolt it too much causing it to crash out as you will still have a high BCLK. Ive always disabled it on big overclocks since the Core2duo's to keep everything level and stable. It will also play with your idle temps as the voltage is pulled from the chip and reapplied dynamically.