Failing to clean your CPU fan can cause the fan to either slow down or to fail completely. If the fan fails, then the temperatures inside the CPU case will significantly increase, which creates the potential for overheating. The easiest way to clean a CPU fan is to use a can of compressed air.
Shut down your PC and turn the power off. Remove the power cords from the rear of the tower and disconnect them from their power source.
Place the tower on top of an antistatic mat that has been laid on top of a table. You may also wear an antistatic wristband that is connected to an electrical ground, like a metal plumbing fixture. You’ll need to use the antistatic devices because static discharge from the floor or from your body could damage data stored on the computer.
Open the back of the computer case according to the directions in your owner’s manual. Some CPU’s will require screwdrivers for removal, while others will have buttons to depress before the back comes off.
Position your can of compressed air at least two inches from the surface that you are cleaning.
Clean the fan intakes and the exhaust using short puffs of canned air. The intakes are the grid-like structures that filter the air that comes into the fan.
Spray short puffs of canned air over the fan blades. To loosen clumps of dirt, hold your canned air at multiple angles rather than using long bursts of air. Make sure that you do not touch anything inside of the CPU tower.
Set the canned air aside and close the back of your CPU.
Clean the exterior of your CPU with a damp cloth that has been dipped in soapy, lukewarm water. Dry the surface with a soft towel.
Use a damp cloth to clean your power cords while they are disconnected from a power source. Dry the power cords with a soft towel.
Return the power cords to their correct positions and power up your computer.