Fan
A computer fan, or cooling fan, cools the computer case by bringing in cooler air and expelling hot air. It can be installed inside or outside the case and works with heat sinks to cool other components. Commonly, axial fans are used, though centrifugal fans are also an option. Cooling fans come in standard sizes and are powered via 3-pin or 4-pin connectors. Recent advancements include improvements in noise reduction, power consumption, and the addition of various styles and lighting effects.
Open-air and blower-style
GPU fans come in two types: open-air and blower-style. Both cool the GPU by bringing in cool air and expelling hot air. Open-air fans draw cool air in and expel heat from the side of the GPU, while blower-style fans use a dedicated channel to expel hot air, drawing cool air through the fan and out of the channel.
Technology
Airflow CFM
Airflow measures the volume of air a cooling fan moves per minute, expressed as CFM (cubic feet per minute) or CMM (cubic meters per minute). Higher airflow improves cooling but may increase noise. CFM is the common unit for fans. Airflow is a key indicator of a fan's cooling capacity; more airflow removes more heat.
Fan speed RPM
RPM (rotations per minute) measures how many times a computer fan rotates in a minute. Fan speed is influenced by factors like motor coils, voltage, blade number, tilt angle, and bearing system. Higher RPMs generally mean better performance, as the fan can move more hot air away and bring in more cold air.
Fan noise
Fan noise, measured in decibels (dB), indicates how loud the fan is. Higher noise values mean louder operation. Noise is affected by various factors and is measured in a soundproof room with less than 17 dB noise, one meter from the fan, aligned with the intake, using A-weighting. A spectrum analyzer is used to record the frequency distribution. Ideally, fan noise should be minimal and free of abnormalities.
Wind Pressure
Wind pressure and volume are interrelated: high volume may reduce pressure and affect heat dissipation, while high pressure can limit volume. Dynatron optimizes fan blade design to balance efficiency and noise by adjusting blade loads, impellers, and guide vanes based on pressure/flow rate.
