Solid yellow
The Dell Diagnostics is running a test, or a device on the system board may be faulty or incorrectly installed.
If the Dell Diagnostics is running, allow the testing to complete.
If the computer does not boot, contact Dell for technical assistance (see Contacting Dell).
it indicates that
The Dell Diagnostics is running a test, or a device on the system board may be faulty or incorrectly installed.
If the Dell Diagnostics is running, allow the testing to complete.
If the computer does not boot, contact Dell for technical assistance .
http://phubner.eng.ua.edu/Files/Optiplex%20745/gethelp.htm#wp1109356
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