Fans are becoming more and more necessary for modern computers. They're used to simply move air through the computer or cool specific components. What more people should realize is that not all fans are the same, and it is a wise choice to select high quality fans that last long, fit your noise tolerance and provide enough airflow for your needs. In this thread I'll make recommendations on fans to choose from, but first lets go over some terms you should know.
Terms and Abbreviations
RPM - Revolutions per minute. Measure of the complete rotations completed by the motor hub/fan blades. The higher the RPM, the more air movement but noise also increases. A more powerful motor is needed to achieve high RPM reliably, therefore motor noise might also increase.
CFM - Cubic feet per minute. Measure of the speed of air movement. Higher means more airflow, but increased RPM leads to increased CFM, therefore higher CFM fans will also be more noisy. The design and amount of fan blades affects CFM as well.
DBA - Decibels. Measure of noise. Higher is louder.
Here is a useful sound chart.
Static Pressure - Measured air pressure. Commonly overlooked. Higher
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