Dell OptiPlex 755 User's Guide - Page 217

I/O Panel Removing the I/O Panel CAUTION: Before you begin any of the procedures in this section, follow the safety instructions located in the Product Information Guide. CAUTION: To guard against electrical shock, always unplug your computer from the electrical outlet before removing the computer cover. 1 Follow the procedures in "Before You Begin" on page 21. 2 Remove the computer cover (see "Removing the Computer Cover" on page 168). 3 Remove the optical drive and floppy drive from the drive bays, if installed (see "Drives" on page 195). 4 Remove the hard drive (see "Removing a Hard Drive" on page 197). 5 Remove the processor heat sink (see "Processor" on page 213). NOTE: You'll also have to remove the heat sink base. 6 Remove the system board. • Unscrew all retaining screws on the system board (see "Small Form Factor System Board Screws" on page 310). • Gently lift the system board out of the chassis. 7 Remove the front fan: Press the tab that secures the fan to the interior base of the computer and lift the fan from the computer; set the fan aside in the chassis. 8 Remove cables from the IO panel. Note the routing of the cables as you lay them aside, so that you can replace them correctly. I/O Panel 217