Your computer's internal fans are important to the overall health of the entire system. One fan cools the CPU, another tends to the power supply unit and one draws heat out of your computer case. If any one of these fans fail, your computer suffers from operational problems, overheating and possible hardware damage. Identifying a failing fan helps you correct the issue before any harm comes to your computer equipment.
The Sound of Silence
As you work and play on your computer, you no doubt hear the comforting whirr of the fans as they keep your machine cool. If the computer is more quiet than usual, one of your fans may have failed. Pay attention to your computer as you use it, and if the fans don't turn on when you feel they should -- such as when you're playing a game or taxing the CPU with a powerful program -- power down before your system overheats.
Too Hot to Handle
One of the most common symptoms of a failed computer fan is overheating and the operational problems that come with it. Every component within your computer tower generates heat as it operates, and this heat is normally disbursed by your case fan through air vents. If your case fan fails, this heat builds and causes increased crashes, Blue Screens of Death and complete shutdowns.
Some helpful computers will actually tell you when one of your fans have failed through an onscreen error message. HP and Compaq desktop systems, for example, offer an error message when they detect a failed CPU fan. This fan, attached to a highly conductive metal object called a heatsink, sits atop the processor chip and whisks away the heat the chip generates. If the fan fails, the CPU can become overheated quickly, possibly causing damage to the delicate chip.
Causes and Solutions
Computer parts don't last forever, and if you've had your computer for a few years your fans may simply be reaching the end of their functional life. Replace them as necessary. An extremely dirty computer or poor placement can cause your fans to work overtime, shortening their lives and eventually causing failure. Open your computer tower and use canned air or lint-free cloths with alcohol to clean any built-up dust, lint or hair that has accumulated on the components and in the vents. Don't position your computer near external heat sources, such as a radiator or sunny window, as these cause your fans to work harder to keep your machine cool. A layer of thermal paste sits between the heatsink and CPU to assist in heat dissipation, and this paste can dry out over time. Replace it to help extend the life of your heatsink and enable it to work more efficiently. If your fans suddenly stopped working after installation of a new program or BIOS update, uninstall and reinstall the software again. Make sure your operating system and hardware drivers are all up-to-date to minimize conflicts.