Saving battery power on iBooks/Powerbooks/...

[Claas Langbehn <claas@rootdir.de>]

Hello,

to whom it might concern...

If you want to save battery power on your iBook / Powerbook
you can add these lines to your /etc/power/pwrctl-local to
make your computer switch the CPU to a lower speed when 
running on battery power. An iBook 500/800 can switch back
to 400 for example.

case "$2" in
ac)
    # set system to high speed
    echo -n "0%100%100%performance" > /proc/cpufreq
    # uncomment the next line if the above does not work
    # cat /proc/sys/cpu/0/speed-max > /proc/sys/cpu/0/speed
    ;;
battery)
    # set system to low speed
    echo -n "0%0%0%powersave" > /proc/cpufreq
    # uncomment the next line if the above does not work
    # cat /proc/sys/cpu/0/speed-min > /proc/sys/cpu/0/speed
    ;;
esac


you can check you the current speed by

# cat /proc/sys/cpu/0/speed

or 

# cat /proc/cpufreq



Bye, claas