Re: cpufreq: powernow-k8 frequency transitions question

[Gunter Ohrner <G.Ohrner@post.rwth-aachen.de>]

Bruno Ducrot wrote:
> I'm wondering if this would have some more power saving if there are more
> low p-states.  I should some day look at this more seriously.

I own a Winchester 3000+ (max. 1,8GHz) which I tried to operate at 800 MHz
(instead of 1,0GHz) but it locked hard. It can be forced to intermediate
out-of-spec speeds (1,2GHz, 1,4GHz and 1,6GHz, although 1,4 should not be
reachable according to AMDs frequency transition spec).

Though I'm not sure if there's any win from these unsupported P-states as
1,0GHz should suffice for most tasks and for everything else the system can
quickly toggle to 1,8 GHz. I currently can't think of any task which would
require more processing power than provided by 1,0GHz but less than
provided by 1,8GHz over a longer period of time, so that the intermediate
P-states would actually be used by the ondemand governor for longer than a
fraction of a second... Though it could be interesting for faster CPUs than
mine that are decoding HD video or similar.

Greetings,

  Gunter

-- 
Ever noticed that people who spend money on beer, cigarettes and drugs 
are always complaining about being broke and not feeling well?        
-- Unbekannter Autor
*** PGP-Verschlüsselung bei eMails erwünscht :-) *** PGP: 0x1128F25F ***