HP ProBook 450 G3 Notebook PC - Maintenance and Service Guide

Heat sink assembly
All heat sink assembly spare part kits include replacement thermal material.
Description Spare part number
Heat sink for use in models with discrete graphics 828396-001
Heat sink for use in models with UMA graphics 830949-001
Before removing the heat sink assembly, follow these steps:
1. Shut down the computer. If you are unsure whether the computer is o 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 rst 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 34).
5. Remove the following components:
a. Service doors (see Service doors on page 35).
b. Optical drive (Optical drive on page 37)
c. Hard drive (see Hard drive on page 39)
d. WLAN module (see WLAN/Bluetooth combo card on page 43)
e. WWAN module (see WWAN module on page 45)
f. Keyboard (see Keyboard on page 48)
g. Top cover (see Top cover on page 53)
h. System board (see System board on page 71)
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)–(6) that secure the heat sink to the system board.
78 Chapter 6 Removal and replacement procedures for Authorized Service Provider parts