HP Pro 3420 Maintenance & Service Manual page 73

6. Disconnect the hard drive power and data cables (2) from the system board.
NOTE: Be careful not to damage the cable when disconnecting it from the board. Do not pull
on the wires.
Figure 7-34 Removing the hard drive connector
7. Remove the connector from the computer.
To install the hard drive connector, reverse the removal procedures.
Hard Drive Cables and Connector 65