HP Compaq dc5100 MT Hardware Reference Manual page 32

Hardware Upgrades
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2–22
6. If replacing or adding a new expansion card, hold the card just
above the expansion slot on the system board then move the card
toward the rear of the chassis 1 so that the bracket on the card is
aligned with the open slot on the rear of the chassis. Gently press
the card straight down into the expansion slot on the system
board 2.
Replacing or Adding an Expansion Card
When installing an expansion card, press firmly on the card so that
the whole connector seats properly in the expansion card slot.
7. If you are replacing an expansion card, store the old card in the
anti-static packaging that contained the new card.
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