The idea, of course, is for the blades to effectively cool the system, but also to make less noise in the process

(I still wouldn't recommend that the average person replace the GPU himself, but then again, the Mac Pro isn't exactly for the average consumer in the first place.)Speaking of thermal performance -- this is the thermal core, after all -- Apple designed a cooling system whereby air is sucked in at the base of the machine, and gets pushed out of that large hole in the top