Dell OptiPlex 755 Quick Reference Guide - Page 67

Power Light Problem Description Suggested Resolution The computer is in a normal off condition or a possible pre-BIOS failure has occurred. The diagnostic lights are not lit after the system successfully boots to the operating system. • Plug the computer into a working electrical outlet (see "Power Problems" in the User's Guide). • If the problem persists, contact Dell (see "Contacting Dell" in the User's Guide). A possible processor failure has occurred. • Reseat the processor (see Processor information for your system). • If the problem persists, contact Dell (see "Contacting Dell" in the User's Guide). Memory modules are detected, but a memory failure has occurred. • If two or more memory modules are installed, remove the modules (see "Removing Memory" in the User's Guide), then reinstall one module (see "Installing Memory" in the User's Guide) and restart 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. • If available, install working memory of the same type into your computer (see "Installing Memory" in the User's Guide). • If the problem persists, contact Dell (see "Contacting Dell" in the User's Guide). Quick Reference Guide 67