Before removing the heat sink, follow these steps:

1.Turn off the computer. If you are unsure whether the computer is off or in Hibernation, turn the computer on, and then shut it down through the operating system.

2.Disconnect the power from the computer by unplugging the power cord from the computer.

3.Disconnect all external devices from the computer.

4.Remove the battery (see Battery on page 46), and then remove the following components:

a.Optical drive (see Optical drive on page 47)

b.Hard drive (see Hard drive on page 49)

c.WLAN module (see WLAN module on page 51)

d.Keyboard (see Keyboard on page 56)

e.Top cover (see Top cover on page 60)

f.System board (see System board on page 74)

g.Fan (see Fan on page 79)

Remove the heat sink:

1.Turn the system board upside down, with the front toward you.

NOTE: Steps 2 and 3 apply to computer models equipped with a graphics subsystem with discrete memory.

2.Following the 1 through 7 sequence stamped into the heat sink, loosen the seven captive Phillips screws (1) that secure the heat sink to the system board.

Component replacement procedures

81