Do not expose your computer to shock. Use only peripheral devices that conform to the computer’s specifications. Connect the devices properly, paying close attention to the condition and position of the connectors. If a connection cannot be made easily, do not apply undue force; check once more to confirm the condition and position of the connector (alignment of pins, etc.) . If the connector has holding screws, fasten the screws firmly. Do not carry the computer with cables attached, and do not pull on the cables forcefully.