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

18.04dellfan

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: