Since both the C519 heatsink and PCB holes are threaded, proper alignment and minimal spacing are crucial during assembly. Carefully align the C519 with the PCB mounting holes, press down firmly until the heatsink touches the PCB, then tighten the screws.
[[File:C519-IMG-9184-1-WiKi.jpg|900px]]
[[File:X1501-IMG-9246-Install.jpg|900px|none|X1501]]