Dell OptiPlex 790 (Early 2011) - Manual (Page 77)

LED
Power Button
Problem Description Memory modules are detected, but a memory configuration or
compatibility error has occurred.
Troubleshooting Steps
– Ensure that no special requirements for memory
module/connector placement exist.
– Ensure that the memory you are using is supported by
your computer.
LED
Power Button
Problem Description A possible expansion card failure has occurred.
Troubleshooting
Steps
– Determine if a conflict exists by removing an expansion
card (not a graphics card) and restarting the computer.
– If the problem persists, reinstall the card you removed,
then remove a different card and restart the computer.
– Repeat this process for each expansion card installed.
If the computer starts normally, troubleshoot the last
card removed from the computer for resource conflicts.
LED
Power Button
Problem Description A possible system board resource and/or hardware failure has
occurred.
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