A fan control apparatus is provided for the computer equipment including a fan, a temperature sensor, and a device module (e.g. an add-in card) mounting at least two devices aligned along an air flow. The fan control apparatus determines a revolving speed of the fan for cooling each device based on an inlet temperature and a usage rate of each device. In addition, the fan control apparatus estimates an inlet temperature of a second device, which is disposed in the downstream side of a first device among at least two devices, based on an inlet temperature and a usage rate of the first device. Thus, it is possible to control the fan to cause an adequate amount of cooling air for cooling devices mounted on the device module installed in the computer equipment.