An electronic assembly may include a chassis, and electronic modules mounted within the chassis. Each electronic module may include a printed circuit substrate, heat-generating electronic components mounted on the printed circuit substrate, and a heat sink body mounted to the printed circuit substrate and having a plurality of heat pipe receiving passageways extending between opposing side edges and overlying corresponding heat-generating components. A respective elongate, passive, heat pipe may extend within each heat pipe receiving passageway and be removably fastened to at least one end to the heat sink body for enhanced conductive heat transport.