I recently purchased this mini-PC. After installing Ubuntu 17.10 the fan speed is set to maximum on boot. I've searched for a solution and found no one.
I found that I can control the fan speed by writting to
/sys/class/thermal/cooling_device0/cur_state an integer value
(in ASCII) from 0 (fan stops) to 11 (fan at full speed).
Also I can read the core temperatures from files
/sys/class/hwmon/hwmon1/tempX_input where X is from 1 to 5.
So I realized that I can write a daemon to control the fan speed in less time than I can find and test a third party solution.
This is my proposed solution.
You need a working compiler sudo apt install build-essential will
install gcc. Then you can compile it
gcc -Wall -pedantic -std=c99 -o vorketempdaemon vorke-temp-daemon.c
sudo mv vorketempdaemon /usr/local/bin
Then as superuser create and/or edit the file /etc/rc.local so it looks like this:
#!/bin/sh
/usr/local/bin/vorketempdaemon
exit 0
make sure it is executable and reboot.
The daemon is working ok. However the fan speed is constantly changing.
In the future it would be nice to implement a hysteresis so the fan speed increments as soon as the temperature goes high but not so inmediately reduce speed when the temperature goes low.