Dell XPS 8500 (Early 2012) - Manual (Page 93)

Chassis Fan
WARNING: Before working inside your computer, read the safety information
that shipped with your computer and follow the steps in "Before You Begin" on
page 13. For additional safety best practices information, see the Regulatory
Compliance Homepage at dell.com/regulatory_compliance.
Prerequisites
1 Remove the computer cover. See "Removing the Computer Cover" on
page 23.
Chassis Fan 93