Ubuntu – Fan switches between full speed and off on Dell G5


I have a Dell G5 5590 with Ubuntu 18.04.4 LTS. BIOS version is 1.11.1.

My fans are constantly switching on and off with a period of 30 seconds (30 seconds full-speed, 30 seconds completely off), even without any processor load. This is very annoying, and I'm not sure it's supposed to be this way, since I'd expect a more gradient fan control.

What I did:

  • I've looked in the BIOS settings, but found no settings related to fan control;
  • I've installed lm-sensors, set it up with sensors-detect and added coretemp to /etc/modules;
  • I've installed i8kutils and ran sudo modprobe i8k force=1, now I'm able to see the fan speed in psensor GUI, as on the picture below;
  • I've installed fancontrol and tried to set it up as described here: https://askubuntu.com/a/46135/762767 – the pwmconfig tool is able to switch my fans off and on during calibration, however, after calibration it says:
No correlations were detected.
There is either no fan connected to the output of hwmon7/pwm1,
or the connected fan has no rpm-signal connected to one of
the tested fan sensors. (Note: not all motherboards have
the pwm outputs connected to the fan connectors,
check out the hardware database on http://www.almico.com/forumindex.php)

Also, even if I finish the pwmconfig setup and run the fancontrol service, there's no change in the fan behavior.

This is how it looks like in psensor:
enter image description here

Best Answer

Please update from BIOS version 1.11.1 to the latest BIOS, 1.12.0, for your Dell G5 5590 laptop, to resolve the fan issue, since control of the fans goes through the BIOS even though there's no controls you can adjust in it (yet).

The latter assertion is based on the first three posts I found with a web search on the subject, which indicate a problem with users runnint Windows 10 as well as Linux; hence my thought the BIOS is involved.