HP Z400 Maintenance And Service Manual page 97

9.
Disconnect the front panel I/O device assembly cables from the system board as shown below.
NOTE:
connector on the system board that you must also disconnect.
Figure 5-11
10.
Carefully guide the front panel I/O device assembly from the chassis.
ENWW
Z400s with 6 DIMM slots have an additional cable from the front panel to the 1394a
Disconnecting the front panel I/O cables
Removing and installing components
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