Dell OptiPlex 990 (Early 2011) - Manual (Page 18)

Installing the Hard Drive
1. Slide the hard drive back into the drive cage.
2. Tighten the screws to secure the hard drive to the drive cage.
3. Install the
drive cage .
4. Install the front bezel .
5. Install the cover .
6. Follow the procedures in After Working Inside Your Computer .
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