Your computer continuously measures the temperature of your CPU. If the temp. goes above a certain point, the computer tells the fan unit to speed up therefore cooling your CPU.
A fan control unit works similar to the thermostat in your home. If the CPU or ambient temperature rises above a certain point, the unit turns on the fan.
A fan control unit regulates the speed at which a fan of your computer rotates. High temperature in your pc (hard working pc) means high speed and more noise.
a fan control unit is what you buy to cool of your computer because if you overheat your computer your computer will break and wont be useable and you might need to buy a new one
