HP Compaq d330 DT Hardware Reference Manual page 26

Hardware Upgrades
✎
2–16
10. Slide the bracket on the end of the expansion card down into the
slot on the back of the chassis 1 and press the card down firmly
into the socket on the system board 2.
Replacing or Adding an Expansion Card
When you install an expansion card, make sure you press firmly on
the card so that the whole connector seats properly in the expansion
card socket on the system board.
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