cpu changes speed when idle

i recently bought a toshiba qosmio f55 with a 2ghz c2d processor. i decided to install cpuz and i noticed that my processor core speed shifts from 1596mhz to 1995mhz randomly and the multiplier goes from x6 to x7.5. for the most part it stays clocked at ~1.6ghz constantly and then going back to its normal speed for a brief moment before downclocking. my power setting is on high performance and i keep the laptop plugged in. there is no bios setting to change the multiplier or fsb so i dont know what to do to fix this problem. any one know whats going on?

 

there is no problem as soon as you need the power, your chip will go to 2.0Ghz. if you don't it scales back. In Windows power managment(vista) you can ajust settings so this doesn't happen if you wish.

 

ah i see, how do i access these properties? i dont see it in power options

 

This is called Intel Speed step technology.
It is perfectly fine for your cpu to dynamically change clock speeds. This is done to obtain a higher efficiency, an lower heat output.

If you want to lock the cpu at different multipliers, you can do so with programs like CPU Rightmark, or Notebook Hardware Control.
Simply go into the cpu profiles, and allow control by p-state transistors, and you can select what multiplier you want your cpu to run at.

K-TRON