HP 4540s C6Z35UT#ABA manual Heat sink, Description Spare part number For use in 4540s models

Heat sink

All heat sink spare part kits include replacement thermal material.

Description	Spare part number
For use in 4540s models:
Heat sink for use in models with UMA graphics	683489-001
Heat sink for use in models with discrete graphics	683490-001
For use in 4440s/4441s models:
Heat sink for use in models with discrete graphics	683655-001
Heat sink for use in models with UMA graphics	683656-001

Before removing the heat sink, follow these steps:

1.Shut down 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 all external devices connected to the computer.

3.Disconnect the power from the computer by first unplugging the power cord from the AC outlet, and then unplugging the AC adapter from the computer.

4.Remove the battery (see Battery on page 42).

5.Remove the following components:

a.Bottom door (see Bottom door on page 44).

b.Keyboard (see Keyboard on page 56)

c.Heat shield (see Heat shield on page 59)

d.Fan (see Fan on page 61)

Remove the heat sink:

1.Position the computer upside-down.

2.To remove the discrete heat sink, in the order indicated, loosen the six captive Phillips screws

(1) that secure the heat sink to the system board.

Component replacement procedures 63