Dell OptiPlex 990 (Early 2011) - Manual (Page 51)

3. Flip over the drive cage and insert it into the chassis. The drive cage tabs
are secured by the slots in the chassis.
4. Slide the drive-cage handle toward the front of the computer into the
locked position.
5. Connect the data cable and power cable to the back of the optical drive.
6. Install the
front bezel .
7. Install the cover .
8. Follow the procedures in After Working Inside Your Computer .
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