Building a personal computer – about fans

There is actually more to fans than big ones can push more air. There are essentially two different styles of fan.

The first type of fan is PWM style. PWM stands for pulse width modulation which is a variable speed fan which is controlled by PWM. These fans have a four pin connection which is used for both powering the fan and controlling the speed. This types of fans can be controlled in a number of ways.

These fans can be controlled by an external switch on the case itself or it can be controlled via the motherboard. Controlled by the motherboard typically means the temperature is being monitored and the fan is being ramped up based on the temperatures received.

The ability to speed up the fans only when needed make them perfect to help have a cool system but also to have a quiet system.

The second type of fan is a static pressure fan. These fans run at a constant rpm and are good for pushing air with some force. This type of fan is typically used for pushing air through radiators where the extra pressure is needed to get through the aluminum fins. Because these fans only run at a specific speed they do not have the same PWM control so they only have a three pin connector.

Selecting a fan

RGB Fans

Up until now I have not been involved with RGB peripherals including fans. RGB fans behave similar to other fans except that they have another lead – a 4 pin connector which will control the colors. Only the colors are controlled by this cable.

This cable cannot be connected to a regular 4 pin fan cable connector but instead of a 4 pin RGB connector. This connector may be on a motherboard but may also be part of separate a RGB controller from another vendor.

Cooler Master


More about fans

I choose a system that was rather limited in the RGB and my motherboard actually does have RGB connections. I choose a few fans that were LED lit but not pure RGB fans. Perhaps in the future I will enhance this aspect.

My case choice was actually rich as far as airflow goes. My case choice, “Phanteks Luxe with tempered glass”, came with four 140mm fans, two in the front, one on top and one in the back. I decided to get a small bit of color so ordered a three led lit fans for on top

Note: These fans are obviously flat so how can you know which direction they are pushing the air? The answer is on the edge of the fan is an arrow showing the direction of airflow.

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