Keep it Cool: Case Fan for Your Computer

With all the processes that go on inside a computer, there is a lot of heat that is produced. This excessive heat needs to be expelled so as to prevent malfunction or damages to the computer. It is here that PC fans come in. They work to dissipate the heat and to bring in cool air into the system. In this way, the temperatures are kept at bay and the overall performance of the computer is enhanced. When getting one, here are some of the things you should know:

What are the types of cooling fans found in computers?

The common types of air cooling fans installed in computers are the CPU fans, hard drive fans, power supply fans, video card fans, and the case fans:

  • CPU fan - To prevent overheating of various components in the CPU, fans are installed inside the CPU. These are used in conjunction with heatsinks that are attached to the motherboard.
  • Hard drive fan - Such kinds of fans are used in systems that produce high amounts of heat from a lot of hard drive usage.
  • Power supply fan - This is located inside the power supply. It blows the hotter air out of the power supply and out of the computer.
  • Video card fan - This fan is located on a video card. It keeps the system cool when playing video games, editing videos or when performing other graphic-intensive tasks.
  • Case fan - Also known as a system fan, a case fan is attached to the front, back or side of a computer case. It draws cooler air from the outside to the inside of the case.

What are the components of a case fan?

A case fan has various components. These include the following:

  • Blade assembly
  • Magnet
  • Bearing
  • Copper wire coil (electromagnet)
  • Fan frame/ stator

In fans with brushes, the magnets are stationary and the copper wire coils are wrapped around the rotating part. Conversely, brushless fans have the magnet rotating and the electromagnet stationary. The latter is the more sophisticated type. The magnet is attached to the blade assembly that has a shaft attached to it. The whole piece put together is referred to as the rotor. The rotor is then mounted onto the fan frame that has the coils installed. In the middle of this piece is a hole, the bearing, where the shaft on the blade assembly is installed.

What should I consider when getting a case fan?

  • Size - Case fans are available in a wide variety of sizes but more commonly you will find 60 mm, 80mm, 92mm, and 120mm square fans with a width of 25mm. You should choose a size that will fit well in the computer case.
  • Airflow - This is the amount of air that is transported by the fan. It is measured in cubic feet per minute (CFM). An airflow rating of 70 CFM is a good one for a 120mm fan.
  • Noise level - Noise does not affect the performance of the cooling fan per say, but it will affect you as the user. It is measured in decibels. Case fans with noise levels below 40 dBA are considered ideal. There are accessories that you can also purchase to help reduce the computer's overall noise levels. Examples are fan corners or dampening sheets.
  • Type of bearing - There are two common type of bearings; the sleeve bearing and ball bearings. Sleeve bearings are basically hollow cylindrical tubes. In this category, you can have fluid dynamic bearings or rifle bearings. Sleeve bearings are initially much quieter but as their lubricant runs out with time, they become louder than the ball bearings. Ball bearings feature balls that separate the moving parts instead of the simple tube. These have a longer lifespan but tend to be louder.
  • Rotational speed - Although other factors such as build quality and the type of bearing affect the noise levels coming from a fan, rotational speeds play a major role. The rate is measured in revolutions per minute (RPM). Generally, the higher the speed, the more the noise that is produced by the fan.
  • Connector - Fans are supplied with voltage either directly from the motherboard or from an external power supply. These connectors can have two to four pins. Fans with four-pin connectors are more common in CPU coolers. For this type, the speed can be regulated with pulse-width modulation (PWM). These PWM signals are typically temperature-dependent.