6 Troubleshooting86No characters appear on screenCheck the following:• Is the keyboard functioning? Test it by turning the “Num Lock”function on and off to make sure the Num Lock light isfunctioning.• Is the video monitor plugged in and turned on? If you are using aswitch box, is it switched to the correct system?• Are the brightness and contrast controls on the video monitorproperly adjusted?• Is the video monitor signal cable properly installed?• Does this video monitor work correctly if plugged into a differentsystem?• Is the onboard video controller enabled in the BIOS?• Remove all add-in cards and see if the video returns. If successful,add the cards back in one at a time with a reboot between eachaddition.• Make sure the memory DIMMs comply with the systemrequirements.• Make sure the memory DIMMs have been populated according tothe system requirements.• Remove the memory DIMMs and re-seat them.• Make sure the processor(s) comply with the system requirements.• Make sure the processor(s) have been populated according to thesystem requirements.• Remove the processor(s) and re-seat them.If you are using an add-in video controller board, do the following:1 Verify that the video works using the onboard video controller.2 Verify that the video controller board is fully seated in the serverboard connector.3 Reboot the system for changes to take effect.4 If there are still no characters on the screen after you reboot thesystem and POST emits a beep code, write down the beep code
