Dell Alienware Area 51 R2 (Late 2014) - Manual (Page 71)

3 Remove the graphics bridge that connects the graphics cards.
1 graphics bridge
4 Starting with the graphics card on the PCI-Express x16 card SLOT1, press
and push the screw covers covering the screws that secure the graphics
card.
5 Remove the screws that secure the graphics card to the chassis.
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