pwmconfig - tests the PWM outputs of sensors and configures fancontrol
pwmconfig will attempt to stop your fans, one at a time, for
approximately 5 seconds each. This may cause your processor temperature to
rise. Verify that all fans are running at normal speed after this program has
exited. pwmconfig does its best to check that the fans are spinning
when they are supposed to, but due to the diversity of available motherboards
and fans, it shouldn't be blindly trusted. Always verify by yourself.
It is strongly recommended to run pwmconfig at a time when
there is no significant system load, to minimize the risk of
pwmconfig searches your sensors for pulse width modulation (PWM)
controls, and tests each one to see if it controls a fan on your motherboard.
Note that many motherboards do not have PWM circuitry installed, even if your
sensor chip supports PWM.
When a connection is established between a PWM control and a fan,
pwmconfig can generate a detailed correlation, to show how a given
fan is responding to various PWM duty cycles.
Lastly, pwmconfig will enter in fancontrol
configuration mode (unless you decide to skip that part.) In this mode, you
are invited to enter several parameters which will determine how the
fancontrol daemon regulates the speed of one or more fans in your
system based on temperature measurements. In particular, you will have the
opportunity to establish mappings between fans and temperature inputs,
define the temperature range over which the speed of the fan should be
adjusted dynamically, the minimum speed at which the fan should spin, etc.
See fancontrol(8) for additional information.
The term "PWM" is used because most fan control systems in computers
are based on pulse width modulation. Some motherboards however use DC
variation instead. So, the term "PWM" should be seen as a generic
term for "fan speed control", regardless of the actual method used.
Marius Reiner <firstname.lastname@example.org>, Jean Delvare