Do you know how lower DC cooling fan noise?
System Impedance should be reduced to the lowest level possible so that the noise to airflow ratio remains low. The inlet and outlet ports of a cabinet can be between 60% and 80% of the total system impedance. This is too high for low-noise results. The impedance of the inlet and outlet could occupy a large fraction of the airflow potential. As a result, a faster and noisier DC cooling fan will be required to provide the necessary cooling.
A rise in temperature may also lead to a reduction in noise. Since airflow has an inverse relationship with temperature, a rise in temperature brings a proportionate decrease in airflow. In any instance where even a small amount of the temperature limit can be slackened may aid in the reduction of noise. Even without temperature changes, selecting a DC cooling fan size will help reduce noise. Large dc cooling fans are quieter than smaller fans that yield the same airflow.
One final approach to reduce noise is to isolate the fan from the cabinet. Because DC cooling fans operate at a low frequency, and are light in weight, vibration isolators must be soft and flexible. This cooling solution is favored in cases where the airflow of the AMD is at less than 20CFM and noise is predominantly from the cabinet.
