Fwd: macbook pro & powertop

[Guillaume Pujol]

Sorry for the double mail Andrea, this was supposed to be on list
(this is early in the morning here :/) ...

---------- Forwarded message ----------
From: Guillaume Pujol <guillp.ml at gmail.com>
Date: 17 juil. 2007 07:28
Subject: Re: macbook pro & powertop
To: "a.biardi at tiscali.it" <a.biardi at tiscali.it>


2007/7/17, a.biardi at tiscali.it <a.biardi at tiscali.it>:
> well, yes, it's good, but not enough: my system still draws about
> 17-18 watt on idle (a mostly black tty in runlevel 1, only necessary
> kernel modules, filesystem mounted readonly, no audio, etc.), whereas
> mac os x gets away with as little as 11 (full functionality, all
> drivers, and graphic environment). so I'm wondering what causes such
> a big difference...

The difference may come from the GPU (Radeon X1600 Mobility), which
oddly doesn't support powersaving under Linux (to be more specific,
the binary blob from ATI doesn't support that feature). This results
in the GPU always being at its full power, about 8 to 10W.
This behaviour only happens on the MacBook Pro Core2Duo from november
2006 (maybe other laptops as well).
See http://www.phoronix.com/forums/showthread.php?t=3130

Regards,