Re: Centrino speedstep

Johan Vromans
2005-01-01T10:50:59Z

Dominik Brodowski <linux-X3ehHDuj6sIIGcDfoQAp7BvVK+yQ3ZXh@public.gmane.org> writes:

> On Fri, Dec 31, 2004 at 01:25:51AM +0000, Pedro Venda wrote:
>> also, how exactly can I use ACPI throttling? because with the speestep
>> driver, I can't go below 600MHz, but 12% of maximum frequency is 180MHz
>> which I can reach using ACPI throttling.
>
> but throttling doesn't save you anything.

Do you have any idea of the actual power savings in relation to
frequency scaling and sleep states? E.g., stepping down from 1.6Ghz to
800Mhz will save a lot (50%?), but how much is saved by using C3
state. More interesting, how much savings are lost by not being able
to use C3 state?

-- Johan