Effect of Dust & Lint Build-up on Cooling Fan and Heat Sink Performance

This document pertains to HP Notebook PC’s, but is relevant to any Electronic Equipment incorporating ‘Forced Air Cooling’.
The electrical components in a PC generate heat, and fans inside the PC help move the air to keep the components cooled to normal operating temperatures. Inadequate cooling can cause excess heat which forces the fan to run constantly, can damage components, and limit the speed of the CPU. All of these problems with high power and high heat will cause applications to work less efficiently than normal.

The sound of the fan running all the time may the first clue that your PC is not running as efficiently as possible and that you may have a problem with accumulated dust clogging air vents or heat sinks fins.

Dust and lint on heat generating components and fans

Notebook PC’s have vents in the bottom and sides to allow air to flow through the case. If these vents become clogged, or heat generating parts become covered with dust, the fan cannot cool the components properly. Lint and dust accumulation prevents air from flowing around the cooling fins and causes the fan to work harder. If there is dust in the vents, you should clean the computer by blowing out the dust from around the fan and heat sink. This will prevent dust from accumulating as shown below.