Acer, Asus, Dell, Hp, Lenovo laptop when in use,Sometimes hear the left side of the machine issued a "squeak" sound, are generally caused by the following two cases.

       One reason: This is the sound of the mechanical hard drive or a notebook cooling fan operation, which is a normal laptop noise, so no need to worry.

       Solution: If it is too noisy, it can be used to disassemble the machine to reduce the fan heat dissipation pressure and reduce the fan noise. The sound produced by the mechanical hard disk is generally very small, almost negligible, of course, you can also replace a more quiet SSD solid state drive.

       Second reason: The noise emitted by high-frequency currents. Some notebooks have been used for a long time, internal components are aging, and humming occurs after leakage.

       Solution: It is best to back up the data and send the notebook for repair. Because this is a hidden danger, it may cause the laptop to suddenly crash. In severe cases it can cause fire.