A heat dissipating system of a personal computer has a heat dissipating unit; the heat dissipating unit including a power supply; the power supply including a housing and a cover; a circuit and a double suction turbine fan being placed in a space formed by the housing and cover; the double suction turbine fan having a casing and a set of blades; an upper and lower surface of the double suction turbine fan having respective air inlets; one lateral side of the double suction turbine fan having an air outlet; one side of the casing of the power supply having air outlets, receptacles, and a power switch; another side of the casing of the power supply having a plurality of holes arranged like a net; a lower side of the cover having a round hole corresponding to the air inlet.