Dell Precision 450 - Manual (Page 30)

7. If you are replacing an AGP card, align the AGP card guide with the base and press down on the indentation until the guide stops at the top of the AGP
card.
8. Connect any cables that should be attached to the card.
See the documentation for the card for information about the card's cable connections.
9. Close the computer cover , reconnect the computer and devices to electrical outlets, and turn them on.
10. If you installed a sound card:
1 filler bracket
2 alignment bar
3 alignment guide
4 retention arm
1 base
2 AGP retention spring
3 indentation
NOTICE: Do not route card cables over or behind the cards. Cables routed over the cards can prevent the computer cover from closing properly or
cause damage to the equipment.
NOTICE: To connect a network cable, first plug the cable into the network wall jack and then plug it into the computer.