I believe they require the same coolers as x79 Socket 2011. Keep in mind if you are going for a Socket 2011 CPU you are going 'high end', and not only that the thermal requirements of the CPU is more demanding. If you are going to the expense of X99, I would go for a good water cooling option like the NZXT Kraken X61, the Noctua NH-D15 may struggle with overclocking and heavier workloads. Don't get me wrong, the Noctua is good, but the other consideration is that if it has to work the fans to keep it cool, it will be louder than a good water cooler.
Sorry, deleted the thread and placed it in Motherboard / Intel CPUs instead. However, the Kraken X61 is nowhere to be found in Europe so I'm not holding my breath for that one. Any other suggestions? I know Corsair have their solutions but I've tried them twice and I've only been burned ...