I have the Noctua NH-D14 for the Asus X79 Sabertooth board. Check their website for clearances, as well as the Asus website. One more thing to consider is the chassis. I bought the Corsair Carbide 500R which has plenty of room and cooling options.
In most cases, even during stress tests with 100% CPU load, the rig is VERY quiet. At normal use I need the fan LEDs in the front to know that the PC is turned on. During 100% stress tests there is a very low humming of the fans, hardly noticeable.
As to memory, search the Internet for compatibility with your board. I had a hard time with my memory or memory settings (and still have since my PC is in the shop for finding the problem). I bought the G.Skill DDR3-1600 9-9-9-24N quad channel 4GBx8 (=32GB) kit. I left the BIOS settings at default which didn't work well and caused random memory or boot issues. It turns out that it needed some BIOS tweaking, mainly enabling XMP. Download your motherboard manual and search for this setting, and search for recommendations for your specific memory kit. Sometimes voltages need to be adjusted as well.
One more advise: Before installing your OS, or right after that, run some extensive stress test together with a memory test to make sure your hardware and settings are stable. Else you may find some unpleasant surprises down the road.