HP Compaq nc6400 Maintenance And Service Manual page 172

Removal and Replacement Procedures
14. If it is necessary to replace the modem connector and cable,
remove the connector 1 from the clip in the base enclosure
and remove the cable 2 from the routing channel in the base
enclosure.
✎
The modem cable is available in the Cable Kit, spare part
number 418876-001.
Removing the Modem Connector and Cable
Reverse the above procedures to install the system board.
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