Dell Precision 490 - Manual (Page 37)

7. Prepare the card for installation.
See the documentation that came with the card for information on configuring the card, making internal connections, or otherwise customizing it for your
computer.
8. If the card is full-length, align it between the plastic card guides on the card fan case.
9. Position the card so that it is aligned with the slot and the securing tab (if present) is aligned with the securing slot.
10. Place the card in the connector and press down firmly. Ensure that the card is fully seated in the slot
If there is a release tab on the card slot, pull the release tab.
11. Before you close the card retention door, ensure that:
l The tops of all cards and filler brackets are flush with the alignment bar.
l The notch in the top of the card or filler bracket fits around the alignment guide.
CAUTION: Some network adapters automatically start the computer when they are connected to a network. To guard against electrical shock, be
sure to unplug your computer from its electrical outlet before installing any cards.
1 card fully seated
2 card not fully seated
3 bracket within slot
4 bracket caught outside of slot
NOTE: For extra security, remove the alignment guide (an upside-down screw) and screw it in right side up to secure a card.
1 card retention door
2 release tab