A computer system including a highly efficient forced air cooling subsystem is disclosed. The computer system includes an enclosure having a first (e.g., front) panel, a processor mounted upon a motherboard located within the enclosure, and a fan located within the enclosure for providing a flow of air through the enclosure. The fan draws air into the enclosure through an opening (e.g., an intake vent) in the first panel and produces a pressurized stream of air. The fan may be oriented such that the pressurized stream of air is directed toward the processor. The computer system may also include a plenum adjacent to the first panel, wherein the intake vent allows ambient air surrounding the enclosure to enter the plenum. The fan may be mounted within an opening in a wall of the plenum. The enclosure may also include a second (e.g., rear) panel opposed to the first (e.g., front) panel and having three openings (e.g., exhaust vents) therein. A first portion of the pressurized stream of air may flow across the processor and exit through a first exhaust vent. A second portion of the pressurized stream of air may flow through a power supply located within the enclosure and exit through a second exhaust vent. A third portion of the pressurized stream of air may flow through a space within the enclosure reserved for option cards and exit the enclosure through a third exhaust vent.