How-To: Troubleshooting Computers
Solution
Try reseating (removing) the RAM if the monitor doesn’t stay on and remains black, even though the system is on.
Push out the tabs on either side of the stick of RAM, it should pop out
Do not touch the gold contacts when handing the component
Put the stick of RAM back in (this takes more force than you’d expect; you know you did it when you hear ‘clicks’ by the tabs on either side of the RAM slot)
Check the BIOS settings.
Make sure the drive you are booting to is high up on the boot order
sometimes it's too low on the boot order
could not be included in boot order at all
Reset the BIOS settings
Swap hard drives with a working computer.
Make sure all video cables are plugged into the add-In graphics card (if the computer has one).
Dell Optiplex 790 systems tend to have a DMS port attached to the graphics card. If one of these systems are needed for whatever reason, we should have an adapter cable for DMS to DVI (one DMS to two DVI), or, you could always take out the graphics card (attached to the DMS port) and use onboard VGA instead (plug a VGA cord into the system).
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