Comment 23 for bug 1514052

Just tried out the kernel as per instructions

Linux HomeMegaUbuntu 4.3.0-040300-generic #201511020949 SMP Mon Nov 2 14:50:44 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

echo 200 > /sys/class/hwmon/hwmon3/pwm1
echo 70 > /sys/class/hwmon/hwmon3/pwm1

results in the erratic fan speed.

if no erratic behaviour wait for a few hours (seems to be about 4 -5hours) and the erratic fan behaviour starts.

to stop it
echo 200 > /sys/class/hwmon/hwmon3/pwm1
echo 70 > /sys/class/hwmon/hwmon3/pwm1

seems to work for me for a few hours before it starts up again.

Interesting that

echo 200 > /sys/class/hwmon/hwmon3/pwm1

results in high CPU fan speed with slow changes in erratic fan (as shown above) superimposed on top of high fan speed.