The faster the cooling fan rotates, the better the heat dissipation effect, but after a period of time, a fan turns slower and slower, and the sound is still very loud, it feels like you have asthma, then your fan must be That is--- First, there is too much dust on the fan blades, which causes the fan blades to be overweight and overloaded---if you have an air gun, then you blow it at him, taking care not to have water. Second, there is no oil in the bearing, or dust has entered the bearing, which has affected the degree of lubrication---this needs to disassemble the fan blade to clean the dirt inside and change the oil. Pay attention to our Yinhai cooling fan. How to disassemble the cooling fan. Buckle 865224937 Third, the shaft is worn out, and the speed will definitely not get up even if the friction increases. Fourth, if the bearing is broken, the material must be replaced. Fifth, the electronic component is broken, you have to ask us to help you. ---Contact me Yinhai cooling fan http://www.yinhaidg.com