From my testing, I believe the only thing that p4-clockmod does is forces an
idle call when it could otherwise do work on an active process, so fullspeed and
idle uses *EXACTLY* the same amount of power as p4-clockmod slower speed and
idle (and therefore generates exactly the same amount of heat), the only power
difference would be that if you were using p4-clockmod to slow down the cpu when
it had an active running process (force the cpu to be idle a lot of the time
even though it has work). Arjan's point is that if you are using p4-clockmod
to slow down an idle cpu in hopes of saving power when the cpu is not being
used, then it is not going to make *ANY* difference in the power usage at all.
I tried it on my p4 here, and cannot see any power difference in idle/fullspeed
and idle/slowspeed, this is unlike the later power saving stuff that actually
does slow down the cpu frequency, and you can measure a different amount of
power usage with the different clock speeds and an idle cpu.
Roger
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