Ball-bearing cooling fans provide better stability and reliability at high speeds and therefore may produce lower noise levels in some cases.

Oil bearing fans usually use grease lubricated bearings, which reduce friction and noise. However, after a long period of use, oil lubrication may gradually consume or degrade, resulting in a gradual increase in fan noise.

In general, the  ball-bearing cooling fan may produce a lower noise level when it is continuously operated at high speed, but the specific noise difference should also consider other factors, such as the design and quality of the fan. At the time of purchase, it is recommended to refer to the technical specifications provided by the manufacturer or user evaluation to choose a low noise cooling fan suitable for your needs.