One of the most interesting CPU coolers in the show, this prototype from Noctua is a sort of an "inversion" of the NH-D14 design. While the NH-D14 has two aluminum fin stacks with room for three fans (intake for the first stack, exhaust for the second stack and one in between the two stacks), this prototype uses three stacks, with two 120 mm Focused Flow fans in between (or any 140 mm fan). So now you have an aluminum fin stack before the first 120/140 mm fan, which conveys air onto a large central stack, from which air is drawn by the second 120/140 mm fan, and onto the third stack which is the size of the first one. Heat is conveyed to the three stacks by eight nickel-plated aluminum heat pipes that pass through the CPU base. The heat pipes that pass through the central portion of the base pass though the central stack, while those that pass though the peripheral portions pass through the peripheral (1,3) stacks. The relatively slim central stack coupled with the high peripheral stacks leave plenty of room for RAM and VRM heatsinks, by up to 70 mm, should be plenty for Corsair Dominator modules. Noctua claims that this heatsink has 20% higher surface area than NH-D14, more surface area is always better.