powernowd and laptop mode

jayc at CLEMSON.EDU jayc at CLEMSON.EDU
Mon Mar 28 16:35:55 CST 2005


On Mon, 28 Mar 2005 21:02:21 +0100 (BST), Paul Sladen
<ubuntu at paul.sladen.org> wrote:

> Anyway, from the tests I've done with my machine I don't think it
> saves that much power. At least the time it gets to go from 45 C to 60
> C (the temperature span where fans are working) seems to be the same
> regardless of it being working at 2533Mhz or ~300Mhz, respectively the
> default cpu speed and the lowest it runs at. Again, maybe these
> savings are better with centrino cpus.

I assume you're using p4clockmod since it's going down to 300 Mhz?  I
never did have good results when I tried it.  Unlike speedstep-ich, it
doesn't scale the CPU voltage, IIRC, which is where a lot of the power
savings comes in.

Is this a laptop that's a P4 but not a P4 M?  I guess P4 M's are the only
ones that can use speedstep-ich?



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