HP ProBook 450 G2, Maintenance And Service Manual, Page: 97 / 169

Heat sink assembly
All heat sink assembly spare part kits include replacement thermal material.
Description Spare part number
Heat sink assembly for use in HP 450 (Intel) models:
For use in models with UMA graphics 768048-001
For use in models with discrete graphics and all processors except for the Intel i7-4558U 768050-001
For use in models with discrete graphics and an Intel i7-4558U processor 768049-001
Heat sink assembly for use in HP 455 (AMD) models:
For use in models with UMA graphics 767435-001
For use in models with discrete graphics 767434-001
Before removing the heat sink assembly, 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 36 ).
5. Remove the following components:
a. Service doors (see Service door on page 37 ).
b. Hard drive (see Hard drive on page 39 )
c. Optical drive (see Optical drive on page 43 )
d. WLAN module (see WLAN/Bluetooth combo card on page 45 )
e. WWAN module (see WWAN module on page 47 )
f. Keyboard (see Keyboard on page 49 )
g. Top cover (see Top cover on page 58 )
h. System board (see System board on page 78 )
Remove the heat sink assembly:
1. Position the system board upside-down.
2. Models are available with either UMA or discrete graphics. The heat sink on discrete models includes 2
additional screws. Refer to the following steps that match your model:
Discrete models:
a. To remove the discrete heat sink assembly, in the order indicated on the heat sink, loosen the 6
captive Phillips screws (1) that secure the heat sink to the system board.
Component replacement procedures 85