Lift the processor-heatsink module straight up from the system board.
16. Set the anti-tilt wires to the locked position.
17. Place the processor-heatsink module on a flat work surface with its contact side facing up.
18. Remove the system board:
a. Loosen the thumbscrew (callout 1).
b. Slide the system board forward and lift it up to separate the system board from the base pan (callout 2).