Troubleshooting the system battery................................................................................................ 136Troubleshooting power supply units................................................................................................137Power source problems.................................................................................................................... 137Power supply unit problems............................................................................................................. 137Troubleshooting cooling problems..................................................................................................138Troubleshooting cooling fans.......................................................................................................... 138Troubleshooting system memory.................................................................................................... 139Troubleshooting an internal USB key...............................................................................................140Troubleshooting an SD card.............................................................................................................140Troubleshooting an optical drive......................................................................................................141Troubleshooting a tape backup unit................................................................................................ 142Troubleshooting a hard drive........................................................................................................... 142Troubleshooting a storage controller.............................................................................................. 143Troubleshooting expansion cards....................................................................................................144Troubleshooting processors.............................................................................................................144System messages.............................................................................................................................. 145Warning messages.......................................................................................................................145Diagnostic messages...................................................................................................................145Alert messages.............................................................................................................................1456 Using system diagnostics................................................................................146Dell Embedded System Diagnostics.................................................................................................146When to use the Embedded System Diagnostics......................................................................146Running the Embedded System Diagnostics from Boot Manager........................................... 146Running the Embedded System Diagnostics from the Dell Lifecycle Controller.................... 146System diagnostic controls......................................................................................................... 1477 Jumpers and connectors................................................................................ 148System board jumper settings.......................................................................................................... 148System board connectors.................................................................................................................149Disabling a forgotten password........................................................................................................ 1518 Technical specifications..................................................................................1529 Getting help.......................................................................................................158Contacting Dell................................................................................................................................. 158Locating your system Service Tag....................................................................................................158Documentation feedback................................................................................................................. 158Quick Resource Locator (QRL).........................................................................................................1587