Abstract: Enclosing arrangements of racks of computing devices fully encloses a space, either solely by the racks themselves, or in conjunction with structural features, such as walls and doors. The enclosed space can be either a hot aisle, whose hot air is vented out by fans positioned in at least one vertical extremity of the enclosed space, such as the floor, or ceiling, or it can be a cold aisle, whose cold air is pumped in by those fans. To maintain proper pressurization across a vertical cross-section of the enclosed space, specific ones of the computing devices have their fans adjusted based on their vertical position within the racks or have passive airflow adjustments, such as impedance screens. Computing devices can draw or vent air from their sides, taking advantage of the interstitial space between the racks provided by the enclosing arrangement.