Core speed change every 20 Sec from 3-2 Ghz

I Just over clocked my e6600 from 2.44ghz to 3.00ghz but with cpuz this what happens
(keep watching) the Core speed




this is with windows Vista




What may cause this ?

Any more information you need that may help i'm welling to give it


HELP.....................

Hey, I just overclocked my q6600 on a Gigabyte 965P-DS3 and had the same problem, and heres whats going on:

There are some settings on the motherboard that drop the core speed when you are not using it as much to save on power and reduce heat, etc. If you go into your bios and go to "Advanced Bios Features" there should be a couple of items on the list towards the middle that all start with "CPU". Here are the ones I have:

CPU Enhanced Halt (C1E)
CPU Thermal Monitor 2
CPU EIST Function

Disable those three and your Core will not drop anymore! Hopefully your settings are the same or close to teh same as mine so it will be easy for you to identify. Another suggestion if you haven't already did it is go into "PC Health" and disable the "Smart Fan Control Method". It just lets your fans connected to the motherboard gain some speed instead of restricting them to low speeds. Hope this helps, if not just write back.

Don't disable the thermal monitor. It's just a thermal monitor it wont downclock your cpu.