Dell Alienware Area-51 R3 Threadripper Edition Service Manual page 56

7. Press the release tabs on the power-cable connectors to disconnect the power cables from the graphics card.
NOTE: The location of the power supply connector (PCIE1, PCIE2 and PCIE3) varies depending on the video card installed.
a. screw cover
b. screws (2)
c. power cables (2)
8. 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.
a. graphics card
b. securing tab
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