Re: AMD's PowerNow?
From: "Mark Brown" <broonie@sirena.org.uk>
> On Tue, Jan 29, 2002 at 12:27:24PM -0400, Derek Broughton wrote:
>
> > As I understand it, speed-step is not supported because it's a typical
> > kludge for Windows. Linux doesn't need it because it idles when not
busy
> > instead of using busy loops.
>
> It's not really a kluge - it's a fairly reasonable idea to drop the CPU
> voltage and clock rate when it's not doing too much. Even if you're
> idling properly when you need to it's still cheaper to run at a lower
> voltage and clock (particularly voltage - the cost of a state transition
> on a transistor is directly related to the voltage it runs at).
Then I must have completely misunderstood about speed-step - I didn't think
it could do anything about voltage. And if you only slow the clock, can you
really get any saving in a busy loop over the use of idle?
derek
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