Contents 7System Board . . . . . . . . . . . . . . . . . . . . . . 94Removing the System Board . . . . . . . . . . . . 94Installing the System Board . . . . . . . . . . . . 964 Troubleshooting Your System . . . . . . . . . 99Safety First—For You and Your System . . . . . . . . . 99Troubleshooting System Startup Failure . . . . . . . . 99Troubleshooting External Connections . . . . . . . . . 99Troubleshooting the Video Subsystem . . . . . . . . . 100Troubleshooting a USB Device . . . . . . . . . . . . . 100Troubleshooting a Serial I/O Device . . . . . . . . . . 101Troubleshooting a NIC . . . . . . . . . . . . . . . . . . 101Troubleshooting a Wet System . . . . . . . . . . . . . 102Troubleshooting a Damaged System . . . . . . . . . . 103Troubleshooting the System Battery . . . . . . . . . . . 104Troubleshooting Power Supply . . . . . . . . . . . . . 105Troubleshooting System Cooling Problems . . . . . . . 105Troubleshooting Cooling Fan . . . . . . . . . . . . . . 106Troubleshooting System Memory . . . . . . . . . . . . 107Troubleshooting an Internal USB Key . . . . . . . . . . 108Troubleshooting an Optical Drive . . . . . . . . . . . . 109Troubleshooting a Tape Backup Unit . . . . . . . . . . 110
