Low noise "Micro Cooling Fan" pressure and air flow are two opposing concepts. Generally, DC cooling fan manufacturer in cost considerations, to design air volume fan, it is necessary to sacrifice some pressure. If the "Micro Cooling Fan" can bring a lot of air flow, but the pressure is small, the wind can not blow the bottom of the radiator (which is why some high fan speed, air volume is large, but the cooling effect is good reason) On the contrary, "Micro Cooling Fan" it often means big pressure on the small amount of wind, there is not enough cold air and heat exchange fins, can also cause poor cooling effect.