A method of controlling a computer system operating under normal conditions, the computer system including a chassis maintaining a power supply unit, a temperature sensor, a central processing unit, and a cooling fan, the cooling fan rated to have a maximum operational speed, the method comprising:
- sensing a power load of the power supply unit;
- sensing a reference temperature of the computer system with the temperature sensor;
- and
- operating the cooling fan at less than the maximum operational speed when the sensed power load is less than a predetermined value and the sensed reference temperature is less than a predetermined value.