Dell Precision 490 Desktop User Manual

Also see for Precision Workstation 490: Quick reference guide Quick reference guide Quick guide Specifications

Contents

Diagnostic Light Codes During POSTThe power light displays a solid green for diagnostic light codes during POST.(blinking)amber A possible failure has been detected in aplug-in component such as a graphics risercard or memory riser card.Verify that any required power cables are connected to the memory and graphicsriser cards.Perform the procedure in Power Problems.(blinking)amber A possible power supply failure hasoccurred.Verify that both power supply cables are plugged in to the motherboard.Light Pattern Problem Description Suggested ResolutionA possible processor failure has occurred. Reinstall the processor (see Processor) and restart the computer.A possible expansion card failure hasoccurred.1. Determine if a conflict exists by removing a card (not the graphics card) and thenrestarting the computer (see Cards).2. If the problem persists, reinstall the card that you removed, remove a different card,and then restart the computer.3. Repeat this process for each card. If the computer starts normally, troubleshoot the lastcard removed from the computer for resource conflicts (see Software and HardwareIncompatibilities).4. If the problem persists, contact Dell for technical assistance (see Contacting Dell).A possible graphics card failure hasoccurred.1. If the computer has a graphics card, remove the card, reinstall it, and then restart thecomputer (see Cards).2. If the problem still exists, install a graphics card that you know works and restart thecomputer.3. If the problem persists or the computer has integrated graphics, contact Dell fortechnical assistance (see Contacting Dell).A possible floppy or hard drive failure hasoccurred.Reseat all power and data cables and restart the computer.A possible USB failure has occurred. Reinstall all USB devices, check cable connections, and then restart the computer.No memory modules are detected. 1. Reseat the memory modules to ensure that your computer is successfullycommunicating with the memory (see Memory).2. Restart the computer.3. If the problem still exists, remove all the memory modules and install one memorymodule in memory module connector DIMM_1.4. Restart the computer.A message appears stating that because your memory is not paired, the system willoperate with reduced performance and reduced error-correction capability.5. Press to boot to the operating system.6. Run the Dell Diagnostics (see Dell Diagnostics).7. If the memory module passes, shut down the computer (see Turning Off YourComputer), remove the memory module, and then repeat the process with the remainingmemory modules until a memory error occurs during start-up or diagnostic testing.If the first memory module tested is defective, repeat the process with the remainingmodules to ensure that the remaining modules are not defective.8. When the defective memory module is identified, contact Dell for a replacement (seeContacting Dell).No memory modules are detected. l If you have one memory module installed, reinstall it and restart the computer (seeMemory).l If you have two or more memory modules installed, remove the modules, reinstall onemodule (see Memory), and then restart the computer. If the computer starts normally,reinstall an additional module. Continue until you have identified a faulty module orreinstalled all modules without error.l If available, install properly working memory of the same type into your computer (seeMemory).l If the problem persists, contact Dell (see Contacting Dell).System board failure has occurred. Contact Dell for technical assistance (see Contacting Dell).Memory modules are detected, but amemory configuration or compatibilityerror exists.l Ensure that no special memory module/memory connector placement requirements exist(see Memory).l Verify that the memory modules that you are installing are compatible with yourcomputer (see Memory).l Reinstall the memory modules and restart the computer.