HP ProSignia 120 Maintenance And Service Manual page 80

5. Remove the modem board retaining screw.
6. Carefully pull the modem board release tab and lift the modem from the computer.
Figure 5-7. Removing the Modem Board
To replace or install the modem, reverse the procedure.
NOTE: When installing the modem, be sure that the modem release tab is folded on top
of the modem before replacing the modem access door.
Removal and Replacement Procedures 5-9