Dell XPS 8500 (Early 2012) - Manual (Page 79)

Postrequisites
1 Replace the optical drive. See "Replacing the Optical Drive" on page 69.
2 Replace the front bezel. See "Replacing the Front Bezel" on page 33.
3 Replace the computer cover. See "Replacing the Computer Cover" on
page 25.
4 Follow the steps in "After Working Inside Your Computer" on page 15.
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