Dell Dimension 5150 Owner's Manual page 74

6 Place the card in the connector and press down firmly. Ensure that the card is fully seated in the slot.
not fully seated
card
fully seated
card
alignment guide
alignment bar
7 Before you close the card retention door, ensure that:
• The tops of all cards and filler brackets are flush with the alignment bar.
• The notch in the top of the card or filler bracket fits around the alignment guide.
74
Removing and Installing Parts
release tab
card retention door
alignment guide
alignment bar
bracket within slot
bracket caught
outside of slot