Dell Alienware Area 51 R2 (Late 2014) - Manual (Page 73)

7 Press and hold the securing tab on the card connector, grasp the card by
its top corners, and then ease the card out of the card connector.
1 graphics card 2 releasing clips
8 Repeat steps 2 to 5 to remove graphics card on the PCI-Express x16 card
connector (SLOT3) and PCI-Express x16 card connector (SLOT5).
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