"220V Cooling Fan" also refers to a DC voltage driven fan. Brush fan through continuous working life in a few hundred to over 1,000 an hour to reach the limit on the use of carbon brushes need to be replaced, or is likely to result in bearing wear. Brush less Fan Continuous Life in general is ten thousand hours to count, and speed can be controlled. Pan used in the production of electronic products for adequate ventilation. "220V Cooling Fan" in the use of the myth is that like? Some users think big fan better results. In fact, using a large fan heat sink effect is not necessarily good, although this fan blades provide a longer, air circulation unit area is large, but it does not mean that ability to take away the heat. Because such "220V Cooling Fan" of speed is usually relatively low, can not be taken away by the heat. Generally, bulky chassis for cooling is beneficial, because it allows more air to flow through the various components.