Hi,
I am currently running a slackware system off of my laptop. I have tried to set it up so that as soon as i remove my AC adapter the CPU throttles down. However, the only way i can get this to semi-work is when i start the laptop up with out the power cord, but then it is stuck at 50% throttled. I was wondering if there is anyway to do this on the fly without having to go to the Power management tab in KDE to manually change it.
Thanks.

Are you familiar with scripting If not I can fool around later, but the idea is to grab the state of the AC Adapter and then depending on the state you can run a command which will change the CPU throttle.

Determing the state of the AC Adapter:

As you can see the state is on-line meaning it's plugged in. You can create the script in two ways: Look for the adapter to be "on-line" or look for the adapter to be "off-line" (not I'm not 100% if it'll be "off-line" just an assumption). Once the script is made and tested you can run it on a schedule (using cron), say every 5 minutes or 10 minutes, and it'll proceed to check if the adapter is present and then throttle based on the state.

I don't know if it's easy to install kpowersave.

You can also work with ACPI daemon. Endless possibilities but difficult...

@CrEsPo: I am not too familiar with scripting, however the second state is "off line".

@ludist: right now i am playing around with the KDE power management so i haven't tried anything else.

Just install cpufreqd.

I do not know if it will help you but I do have my Athlon set up to drop to 50% depending on demand


Uncomment in the conf file ( sorry I am away from my PC and cannot remmber the name)

/sbin/modprobe powernow-k8
/sbin/modprobe cpufreq-ondemand

put in rc.local

if [ -f /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor ]; then
echo -n "Setting Scaling Governor : "
echo -n ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
echo "ondemand"
fi