An apparatus, system and method for cooling vertically stacked printed circuit boards (PCBs). In one embodiment, a first PCB is disposed within a substantially enclosed lower chamber inside a PCB containment housing. A second PCB is disposed above the first PCB within the housing to define a substantially enclosed upper chamber above the lower chamber. The second PCB includes one or more airflow apertures defined therethrough and providing vertical air flow coupling between the upper and lower chambers. An airflow actuating device is utilized to generate a primary forced airflow within the upper chamber which is substantially parallel to the surface plane of the second PCB. The primary forced airflow further induces a negative air pressure in the upper chamber such that a mixed convection airflow is established between the upper and lower chambers via the second PCB apertures.