On my laptop (W7, C2D T6400) is all ok, config shows CPU speed changes depending on cpu load.
It also worked on my old PC (W7, C2D E8400) - it showed real CPU speed.
Recently i upgraded my hardware and now i have i5 2500K - now my config shows all the time only default CPU speed, even when oc'ed.
What is wrong?
This is a known issue with PowerPlugin and Intel processors with Turbo Boost. The plugin queries the frequency directly from Windows, so this is a problem with Windows itself.
You may want to try the SpeedFan, CoreTemp, or Open Hardware Monitor plugins although they do require the presence of the aforementioned programs.