Does overclocking lock a CPU to one frequency thereby loosing power saving throttling features?

I've just ADDED some extra cooling HEAD room and I was wondering if this would be a sacrifice? Or I could just have completely misunderstood how throttling works Assuming it is done correctly it won't, worst case when the CPU clocks itself down automatically it may clock down to a slightly higher SPEED than it did before.

In my BIOS there is a setting for turning the turbo "Throttling" on and off.My AMD that I have a 10% overclock on with Cool'n Quiet enabled in bios does just as Camerongrey stated. It throttles back when idle, but to a higher clock than that of the clock that it would run at if without overclock.

I overclocked a AMD Athlon 64 X2 4450B 2300Mhz CPU to 2530Mhz.

With Cool'n Quiet enabled the CPU at normal clock and throttled back when idle shows like 600Mhz, and with the overclock via increasing my FSB on my RAM from 200Mhz to 220Mhz for 10% overclock, its idle at like 660Mhz.