Dell Alienware Alpha (Late 2014) - Manual (Page 44)

Procedure
NOTE: The original thermal grease can be reused if the original video card
and heat sink are reinstalled together. If either the video card or the heat
sink is replaced, use the thermal grease provided in the kit to make sure
that thermal conductivity is achieved.
1 In sequential order (indicated on the heat sink), loosen the captive screws
that secure the video-card heat sink to the system board.
1 video-card heat sink 2 captive screws (4)
2 Lift the video-card heat sink off the video-card heat sink.
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