Fighting for the power.

Alexander Motin mav at
Mon May 4 03:45:15 UTC 2009

Adam McDougall wrote:
> On Mon, May 04, 2009 at 01:18:14AM +0300, Alexander Motin wrote:
>   I would like to summarize some of my knowledge on reducing FreeBSD power
>   consumption and describe some new things I have recently implemented in
>   8-CURRENT. The main character of this story is my 12" Acer TravelMate
>   6292 laptop with C2D T7700 2.4GHz CPU, 965GM chipset and SATA HDD, under
>   amd64 8-CURRENT.
> Great list!  May I suggest screen brightness and DPMS as another tool
> to save power, I've measured a 5W difference from the screen draw.
> Keeping the brightness as low as tolerable helps considerably, but 
> also using 'xset dpms 120 120 120' (modify to taste) in .xinitrc to
> turn off the screen after 2 minutes helps when the laptop isn't being
> used every second.  May need this in xorg.conf:
> Option             "dpms"

Yes, backlight is also important. But there is not so much things could 
be done.

When I am leaving system for some time, I can just close the lid, if not 
put system into S3 state, which require very small power (at least I was 
unable to really measure it without all-day-long testing). Thanks to 
jkim@ we have more or less working S3 state for amd64 now.

Alexander Motin

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