HP Apollo 4200 Gen9 User Manual page 59

Remove the rear option blank.
6.
Retain the blank for future use.
Install the four-bay LFF hot-plug rear drive cage:
7.
Align the pins on the drive cage with the notches on the rear panel.
a.
Tighten the thumbscrews to secure the drive cage to the rear panel.
b.
Tighten the captive screws to secure the drive cage to the system board.
c.
Connect the power Y-cable:
8.
Connect the common 5x2 connector to the system board.
a.
Hardware options installation 59