Noctua is one of the last bastions of high-performance top-flow design CPU coolers, but that doesn't come in the way of Noctua keeping top-flow alive, in fact the company is coming up with more ways to push the performance barrier, and compete with side-flow and closed-loop water cooling kits. Seen here is a new "downdraft" type CPU cooler prototype. The design involves large aluminum fin stacks that propagate along the plane of the motherboard, over the CPU socket and memory slot area. Don't worry, there's 70 mm of clearance with everything below, letting you install certain kinds of tall memory modules. The heatsink, with its 25 mm thick fans installed isn't much higher than most high-end side-flow tower type heatsinks. The design involves a CPU base from which 7 nickel-plated copper heat pipes shoot up a height of 70 mm, before passing through the two fin stacks. The surface area of this heatsink is said to be 20% higher than that of the NH-D14. The heatsink is ventilated by two 120 mm Focused Flow fans, blowing air downwards. Everything else on the upper-half of the motherboard (such as VRM), gets cooled under the air-flow.