HP ZE4900 - Manual (Page 115)

5–32 Maintenance and Service Guide
Removal and Replacement Procedures
2. Disconnect the fan cable 1 from the system board.
3. Remove the 3 PM1.5×5.0 screws 2 that secure the heat sink
to the notebook.
4. Remove the heat sink 3.
Removing the Heat Sink
✎
Carefully clean any thermal pad residue from the heat sink and
processor surfaces each time you remove the heat sink. Install
a new thermal pad.
A thermal pad is included with the replacement heat sink and
is also available using spare part number 371809-001.
Reverse the above procedure to install the heat sink.