"Micro Cooling Fan" blower to achieve the purpose, the need for static and dynamic pressure. Full hydrostatic and hydrodynamic pressure is the algebraic sum of the total pressure is the difference between the total pressure of the fan given the increased amount of the total pressure, the fan between exports and imports. "Micro Cooling Fan" in practice, the nominal value of maximum wind is not blowing fan heat sink to get the actual amount of wind capacity, not on behalf of the ventilation ability. Due to air flow, air flow in its path will encounter obstruct fan heat protracted sheet or element, "Micro Cooling Fan" impedance will limit the free flow of air. That is when the wind increases, air pressure decreases. Therefore, there must be an intersection of optimal operating working point, namely wind cooling fan performance curve and drag the curve.