Dell OptiPlex 990 Desktop Service Manual page 77

LED
Power Button
Problem Description
Troubleshooting Steps Remove the coin cell battery for one minute, reinstall the
LED
Power Button
Problem Description
Troubleshooting Steps
LED
Power Button
Problem Description Memory modules are detected, but a memory failure has
Troubleshooting
Steps
– If the problem persists, the system board is faulty.
A possible coin cell battery failure has occurred.
battery, and restart.
A possible processor failure has occurred.
Re-seat the processor.
occurred.
– If two or more memory modules are installed, remove
the modules, then re-install one module and re-start the
computer. If the computer starts normally, continue to
install additional memory modules (one at a time) until
you have identified a faulty module or reinstalled all
modules without error.
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