Fan speed tuning

Fancontrol is used, under GNU/Linux OSs, to set fans' speed in realtime, depending upon device Temperature.

To enable fancontrol you have to generate a config file ... let's see how.

First of all, stop the fancontrol daemon if it's running:

# /etc/init.d/fancontrol stop

Now we use the 'pwmconfig' tool to create a config file for fancontrol to use:

# pwmconfig

You'll be shown some info about the process that is going to take place after hitting 'Enter': this process includes probing all the system fans in order to understand which ones may be controlled by fancontrol. When a configurable fan is found, you'll be told that, if you accept (y), pwmconfig will test all the possible speed values your fan can work with: this means that first of all the given fan will be taken to max speed and then progessively slowed down to minumin speed and finally set to max speed again (the process takes about 20-30 seconds: generally speaking, no harm should result to your device as a consequence of slowing down the fan for such a little time).

Once all of this as ended, you can finally set up fan behaviour based on read Temperatures:

from the prompt chose the pwm device you want to configure, then chose which temperature sensor fancontrol should associate to that pwn device (if you want to adjust your CPU Fan, than run

$ sensors

in a terminal and look for the CPU Temperature sensor name: the same name will be listed by pwmconfig). Follow the remaining steps (you have to enter some values, like the Min and Max Temp for the given device: wrong settings could harm your CPU, so be careful adjusting these values) save the profile and continue selecting another pwm device, or save & quit if you're fine.

Now look at /etc/fancontrol : this is the config file that our daemon is going to use after we start it:

# /etc/init.d/fancontrol start

If you're not satisfied with the actual configuration and say you want to change some parameters, you'll have to restart this procedure from the beginning.