dell-bios-fan-control

A user space utility to set control of fans by bios on Dell 9560 (and
some other Dell) Laptops.

Use by dell-bios-fan-control 1 to let BIOS control fan speed (default),
and dell-bios-fan-control 0 to turn BIOS control off.

Presumably, you need to turn it off in order to let i8kctl or some other
userspace fan speed daemon do the job.

Just leaving it off without any control might overheat and damage your
computer.