Typically, CPU fan noises are heard when you reboot your PC (the whirring sound you may have heard upon startup) and it goes on to decline as the startup process completes. The purpose of fans on your ...
A CPU fan is more than just a fan. It is attached to CPU with power pins/wires and a sensor that tells it how fast to run. If the CPU is heating, the sensor will make the fan run faster. As such, the ...