"Waterproof Cooling Fan" temperature; small fan supply temperature will be lower, and will avoid the presence of airflow dead zone at the top of the chassis. If you are under the power of the chassis, a large windmill fan directly into the wind from the outside of the chassis, power supply will be very cool, is conducive to a stable power supply, extend "Waterproof Cooling Fan" life, but dust will be relatively large; small fan power will not very cool, but it will not become cleaner. Some people like to set a large windmill power under the anti-wear, are interested can try. For fanless power supply, the positive pressure in the duct of the chassis, most of the heat will be discharged to the outside of the chassis; suction duct within the chassis, most of the heat will be discharged to the chassis. And "Waterproof Cooling Fan" a large number of openings will supply chassis air duct design brings some inconvenience, need special attention.