Replacing the system battery........................................................................................................57Hard-drive backplane......................................................................................................................... 58Removing the hard-drive backplane............................................................................................ 58Installing the hard-drive backplane..............................................................................................60Control panel assembly...................................................................................................................... 61Removing the control panel......................................................................................................... 61Installing the control panel........................................................................................................... 62System board.......................................................................................................................................63Removing the system board......................................................................................................... 63Installing the system board........................................................................................................... 654 Troubleshooting your system..........................................................................66Safety first—for you and your system................................................................................................ 66Troubleshooting system startup failure............................................................................................. 66Troubleshooting external connections..............................................................................................66Troubleshooting the video subsystem...............................................................................................66Troubleshooting a USB device........................................................................................................... 66Troubleshooting a serial I/O device................................................................................................... 67Troubleshooting a NIC........................................................................................................................67Troubleshooting a wet system........................................................................................................... 68Troubleshooting a damaged system..................................................................................................68Troubleshooting the system battery.................................................................................................. 69Troubleshooting power supplies........................................................................................................69Troubleshooting cooling problems....................................................................................................70Troubleshooting cooling fans............................................................................................................ 70Troubleshooting system memory...................................................................................................... 70Troubleshooting a hard drive.............................................................................................................. 71Troubleshooting a storage controller................................................................................................ 72Troubleshooting expansion cards...................................................................................................... 72Troubleshooting processors...............................................................................................................735 Using system diagnostics.................................................................................. 74Dell online diagnostics........................................................................................................................74Dell embedded system diagnostics....................................................................................................74When to use the embedded system diagnostics......................................................................... 74Running the embedded system diagnostics................................................................................ 75System diagnostic controls........................................................................................................... 756 Jumpers and connectors.................................................................................. 76System board jumper settings............................................................................................................ 76System board connectors................................................................................................................... 77Disabling a forgotten password..........................................................................................................79