A plenum (12, 60) having a plurality of heat fins (40, 72) and also a receptacle (20) for receiving a heat generating component (22) in a friction fit arrangement. The plenum has a plurality of passageways (14, 66) defined by the plurality of fins arranged in rows, and also includes a plurality of openings (50, 76) disposed between the fin. The receptacle frictionally receives a respective heat generating component (22), and wicks heat to the fins. Air communicating through the passageways defined by the fins removes heat from the fins, and also creates a venturi effect to remove heat from within a housing via the openings to further cool the portable electronic device.