5Troubleshooting your systemSafety first—for you and your systemCAUTION: Many repairs may only be done by a certified service technician. You should onlyperform troubleshooting and simple repairs as authorized in your product documentation, or asdirected by the online or telephone service and support team. Damage due to servicing that isnot authorized by Dell is not covered by your warranty. Read and follow the safety instructionsthat came with the product.Troubleshooting system startup failureIf you boot the system to the BIOS boot mode after installing an operating system from the UEFI BootManager, the system hangs. The reverse is also true. You must boot to the same boot mode in which youinstalled the operating system.For all other startup issues, note the system messages that appear on the screen.Troubleshooting external connectionsEnsure that all external cables are securely attached to the external connectors on your system beforetroubleshooting any external devices.Troubleshooting the video subsystem1. Check the system and power connections to the monitor.2. Check the video interface cabling from the system to the monitor.3. Run the appropriate diagnostic test.If the tests run successfully, the problem is not related to video hardware.If the tests fail, see Getting Help.Troubleshooting a USB deviceAbout this taskUse the following steps to troubleshoot a USB keyboard/mouse. For other USB devices, go to step 7.Steps1. Disconnect the keyboard and mouse cables from the system and reconnect them.2. If the problem persists, connect the keyboard/mouse to the USB port(s) on the opposite side of thesystem.129
