I find that when I try to plug in any USB device into the USB ports , the windows would give sound, even if the USB device is not plugged into, just the edge of the connector touches the port. Why would that happen? Is it bad to portable HDD?
The motherboard detects USB devices by monitoring power draw on the port, if you create a circuit or a short the BIOS instructs the OS to a hardware change, windows makes a noise and searches for the device. The USB detected noise can be heard even when a "charging only" usb cable is connected (no pins/wires for data). This will either result in windows saying nothing more about the device or returning an error. As to whether it will damage a portable HDD it's unlikely, however possible with mechanical drive. Solid state/flash drives will be safe. If the connection is only brief the drive wont even have time to spin up so will not be damaged crashing down. If the connection is loose, either use a back panel port or replace the front panel connector.
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