Re: enhanced intel speedstep feature was Re: speedstep-centrino on dothan

[st3@riseup.net]

On Thu, 7 Jul 2005 16:06:48 -0400
Dave Jones <davej@redhat.com> wrote:

> On Thu, Jul 07, 2005 at 10:00:27PM +0200, st3@riseup.net wrote:
>   > Enabling, say, a duty cycle of 12.5% means that the CPU chip will be driven
>  > by clock just one time every eight, thus reducing power consumption and
>  > temperature (and it speeds down dramatically the CPU, too =).
>  > 
>  > I tested it so far on my Pentium M Dothan 715 and on a Dothan 725.
>  > 
>  > What do you think, could this be useful? I could provide a patch or a
>  > stand-alone module. Should I write an interface to sysfs?
> 
> You just reinvented the p4-clockmod driver :-)

Oops. =)

> This hasn't been seen to save any power whatsoever that I've seen.

It drops down power rating by 1500-1800mW on my Toshiba Satellite A50
while idling at 400MHz.

> I've heard a few reports that it reduces heat for a few folks, but
> betting on it increasing your battery life is probably a push.

Just a latest question: can be p4-clockmod used together with
speedstep-centrino? If not, would it make any sense to patch
speedstep-centrino to use this feature too?


--
ciao
st3

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