[ltp] Bad fan behaviour in X61s caused by GPU temperatur sensor

[Tino Keitel]

Hi folks,

I noticed that the fan in my X61s is started whenever the temp4 sensor
reaches 40°C. According to the thinkpad-acpi documentation, this is the
sensor for the GPU. It's value also goes up when I start glxgears in
fullscreen mode.

The bad thing is, that the temp4 sensor causes the fan to be nearly
always running, unless I stop X.  I already disabled compositing, and
switched to 16 bit color depth, without success.  The thing is, I just
can't believe that mobile hardware has to be cooled by a fan at 40°C
already.  However, I also don't want to run any fan script control
scripts, as I tend to trust the hardware vendor more than some script
writers.  :-)

So, is this normal behaviour? Any hints how to avoid the fan to be
running that often?

Regards,
Tino