Well the picture is that of an Apple Fan on the Power supply. These help some by moving the air around in the case. These are a little noisey. A System Saver IIgs says that right on the left side the buttons on the right side. The fan sucks the air straight up. Auxiliary plugs are on the back of the unit. One fan to move the air around inside and one to pull it out works really well if the IIgs is loaded.