To solve this problem, we can try to use larger cooling fans. Under the condition of the same air volume, the working noise of the fan with large size at lower speed is smaller than that of the fan with small size at higher speed.

Another factor that we easily overlook is the bearing of the cooling fan. Because the rotating shaft and bearing collide with each other when the cooling fan rotates at high speed, it is also a main source of noise of the cooling fan.