Step 40
Due to variations between iBook G4 models, your heatsink may have either 5 or 6 screws. We've noted all possible positions for screws in the step below. If there's no screw to remove, then skip to the next screw. Be sure that you remove all necessary screws before attempting to remove the heat sink.
Remove the following 6 screws and 3 nuts from the heat sink:
One 2 mm Phillips extending from a finger on the left edge of the heatsink and adjacent the firewire port (not present on some models)
Three 3 mm Phillips from around the fan (some models may only have 2 screws).
One 3.5 mm Phillips on the left side of the heat sink (not present on some models).
One 4.5 mm Phillips at the top right corner of the heat sink.
One 6 mm Phillips at the lower left corner of the heat sink.
One 4 mm nut from the right side of the heat sink.
Two 4 mm screw nuts with attached springs from either side of the heat sink.
Step 41
It may be necessary to soften the thermal paste between the logic board and heat sink. You can soften the thermal compound using a hairdryer. Move the hairdryer back and forth over the ribbed metal section of the heat sink for one minute. At this point, the heat sink should come free easily.
Use a spudger to pry the heat sink up on the left side, near the hard drive.
Step 42
Grasp the heat sink in one hand and lift up the hinge grill in the other hand so that you can remove the heat sink from the computer.