[Mageia-discuss] Why would runlevel 3 take more power?

[Maarten Vanraes]

Op maandag 03 oktober 2011 03:35:44 schreef Norman Carver:
> Set up a new server for home use (DNS, files, etc.) and
> was gratified to find it using around 50 watts when the
> older machine it replaces was using around 90.
> However, just before sticking it in the closet, I changed
> it to runlevel 3 since I won't be using the GUI typically.
> I had assumed this might reduce power usage a bit
> more, but surprisingly it caused the power draw to go UP
> by about 3 watts!  I thought it a fluke, but verified that
> this is a real phenomenon:  the machine draws about
> 3 watts less when X and KDE are running than when
> they are not.  Seems like running more processes should
> cause more power usage.  Any ideas what might be
> causing what I see?  Odd.
> 
> I note that:
> (1) I set kernel scaling_governor parameter for
> each core to ondemand for any runlevel;
> (2) whether logged into KDE or just sitting at the
> DM the power usage is stabilizes at the same level
> when in runlevel 5;
> (3) I have not made any power settings in KDE and
> the power applet is not running;
> (4) runlevel 5 has all the same services as runleve 5
> plus: dm and atieventsd.
> 
> Thanks for any insights!
> Norm

Perhaps when X and KDE is running, existing processes have less CPU time, due 
to it and these processes take more power/CPUcycle than X/KDE?