Frequency takes more power so you will find higher frequency processors
Frequency has very little meaning in power consumption. My dual core 4200+
draws less power with 2 cores running at 2.2Ghz than my older single core
3000+ running at 2.0Ghz. The only time you'll see a noticeable increase in
power consumption is when you increase the core voltage.
That is correct - higer frequency processors draw more power because their
voltage is usually
set higher. If you increase the voltage on an idle cpu, you will see the
power consumption increase - dramatically. A change of .1 v can make a big
difference.
Changing cpu frequency by itself doesn't make a huge difference. Try it on
an idle cpu, or one with a constant load, and watch what happens - power
consumption will not change very much. Then bump the voltage up or down by
..1v and watch power consumption significantly change.
I have a Phenom 9950 2600MHz. I can ratchet the cpu down to 1000MHz, and
power consumption changes by maybe 5%. If I then drop the voltage by .3v,
power consumption drops by about 20%. Likewise, boosting the cpu to 2800MHz
makes no noticeable change in power consumption. And surprisingly, it's rock
solid without having to change the voltage any.