The heatsinks come from Arctic pre-assembled with the fans, the whole unit is just placed on the ASIC and affixed with the custom aluminium bracket.
wait what about paste??? just some pre-paste on these? that would explain why some modules are hotter than others beside the other 10 reasons we have talked about
What are you on about? each chip is pasted prior to assembly an the manufacturing facility. They have a special metal grid that lies flush on top of the chip and the paste is spread thinly over.