Turn off and unplug your computer. Also, disconnect all cables and peripherals from it, such as a monitor cable, printer cable, Ethernet cable, keyboard and mouse cords, and any other USB-connected devices such as external hard drives. Pick up the computer carefully and gently rock it side to side. If you hear a rattling sound, a screw may have come loose and is rolling around inside your case. A few light shakes will usually knock it loose and into the bottom of the case where you can find it. If the screw is lodged somewhere that you can’t reach with your fingers, try using a long pair of tweezers or needle-nose pliers to reach it. While the computer is off and unplugged, open the case and inspect all of the cables inside the computer. Look for stripped, naked, or frayed wires. If any are found, replace them immediately, even if they don’t appear to be touching any components; they may not be causing a problem now, but they will likely cause problems in the future. Also, check wire twist ties and any other wrapped metal bindings that might currently be used for cable organization. While most of these are now all plastic, some are metal and will wear over time, exposing metal.
