Why is Computer Fan so Loud?
The latest computers have temperature sensors which are monitored by a separate circuit. This circuit keeps track of the temperature and if this goes up, then it triggers the fan to increase the speed. Sometimes the heat sinks will get filled up with dust and deny controlling the heat properly. This makes the fan to compensate for the lack of heat dissipation. By clearing the dust in the heat sink it might help us a long way in avoiding the fan sound. Taking care to control the temperature rise can also make the fan not to make much noise.
There are two main reasons if not anything mentioned above responsible for the fan to make the noise. The two reasons are disk drives and cooling fans. There are 3 fans in the computer. They work to bring in cool air and send away hot air. If the fan fails in cooling the system, one of the indicators is that it makes noise. We can remove the noisy fan and replace it with the better one. However, this can also be solved by applying Sewing machine oil which is commonly available in the households.
Two microscopic ball-bearings are used in the computer fans to offer support on both sides of the main shaft. Some small size fans will have sintered metal bearings. These bearings are cylindrical porous elements which have spaces in them which contain the lubricating oil. This oil gets released into the metal bearings and circulates around the fan shaft which is rotating inside the bearing. These bearings might get worn out suddenly and they have to be lubricated if the fan makes noise. If the fan loses lubrication, it makes noise. More expensive or big fans rarely fail to work or make noise. When the original mineral oils present in the bearings are lost, they should be replaced with lubricants again in order to avoid the loud noises made by the computer fans.