The invention provides forced-air cooling to components mounted on circuit boards oriented in a side-to-side direction in a system. Airflow may enter and exit the system through the front and back (or vice-versa), rather than the sides of the system. In one embodiment, airflow entering the front of the system is re-directed in an upward direction, then split to form airflow branches traversing in a side-to-side direction. The airflow branches traverse across the surfaces of circuit boards, then are directed in an upward direction and out the back (or front) of the system. The airflow branches preferably move substantially the same volume of air per unit of time.