Dell Vostro 1550 (Mid 2011) - Manual (Page 39)

Removing The CPU Fan Assembly
And The Heatsink
15
1. Follow the procedures in Before Working On Your Computer .
2. Remove the battery .
3. Remove the keyboard .
4. Remove the palm rest .
5. Disconnect the CPU fan cable from the system board.
6. Remove the captive screws that secure the heat sink and CPU fan
assembly by following the sequence in the image.
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