Dell Vostro 270 (Late 2012) - Manual (Page 11)

4. Remove the screws that secure the fan to the back of the computer.
5. Remove the fan from the computer.
Installing the System Fan
1. Place the fan at it's location on the computer.
2. Replace the screws that secure the fan to the back of the computer.
3. Connect the fan cable to the system board.
4. Replace the cover.
5. Follow the procedures in After Working Inside Your Computer .
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