HP ProDesk 400 G3 Small Form Factor Maintenance And Service Manual page 29

5. Before installing an expansion card, remove the expansion slot cover or the existing expansion card.
NOTE: Before removing an installed expansion card, disconnect any cables that may be attached to
the expansion card.
a. If you are installing an expansion card in a vacant PCI Express x16 socket, remove the appropriate
expansion slot cover on the back of the chassis. Pull the slot cover straight up then away from the
inside of the chassis.
b. If you are installing an expansion card in a vacant PCI Express x1 socket, insert a flatblade
screwdriver into the slots on the rear of expansion slot cover (1) and rock the slot cover back and
forth to break it free from the chassis (2).
Expansion card 21