Quality "Micro Cooling Fan", its center of gravity in the axial fan blade, working very smoothly, very little noise, and defective electric fan, there is often a certain error, the focus of the blades is not formed in the axial " eccentric ", after such a fan transition up to the equivalent of one oscillator, followed by the use of time longer,"Micro Cooling Fan"gradually bearing wear, or fan heat sink device is not strong, showing loose, will make sensation aggravating noise becomes large. Such illnesses most simple solution is to try to fan means strong, so that does not stir up, of course, this approach does not solve the substantive problem, since the fan blades still "eccentric"; Another approach is to "Micro Cooling Fan "oiling the bearings, to cushion the effects of sensation, then weaken noise;