"Micro Cooling Fan" of life by motor life, environment, power supply and other factors of the composition. Air in the form of the most widely used form of axial fan is blowing down, the reason why so popular is because the combined effect of good and inexpensive. If the direction of the axial fan in turn, becomes upward ventilation, especially in certain models of the radiator will use this form. The difference is that the two forms of air flow in the form of different turbulence is generated when the blast, but susceptible to wind pressure resistance big loss; "Micro Cooling Fan" is generated when the laminar flow ventilation, air pressure small but steady flow . In theory, the turbulent heat transfer efficiency is much greater than the laminar flow, and therefore did not become mainstream design form. But the flow of movement and the heat sink has a direct relationship. In some heat sink design, airflow obstruction by very large heat sink, then the use of ventilation may have better results. The only problem with the design of the side of the blast, not usually at the top of the blast and the effect of any difference. The "Micro Cooling Fan" more effective approach is to establish an improved dedicated CPU cooling duct, so they are not affected by the hot air near the CPU, the equivalent of reducing the ambient temperature.