Around "Micro Cooling Fan" is nothing more than a few factors that several major factors voltage, current, power, speed, noise, and the like. I believe that many customers want to buy low noise, large air volume of axial cooling fan, but 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 ventilation ability. Due to air flow, air flow in its path will encounter obstruct fan heat protracted pieces or elements, the impedance will limit the free flow of air. That is when the wind increases, air pressure decreases. Therefore, there must be an optimum operating point operations, namely intersection "Micro Cooling Fan" performance curve and drag the curve. At the operating point, the slope of the characteristic curve of the fan to a minimum, change the system characteristic curve was the lowest. Note "Micro Cooling Fan" static efficiency at this time (the amount of wind power ÷ × pressure) is the best. Of course, control to this point is very difficult, no longer experience simply will not be completed.