ROG community member, Chino, has put together a Windows install guide for M.2 SSD owners on his Rampage V Extreme (although it will also work with Maximus VII boards featuring M.2 slots as well).
It covers BIOS settings, UEFI/non-UEFI install and suggestions on how to work with Samsung's popular XP941.
"Installing Windows isn’t exactly rocket science. Most of us have probably gone through this process more than once in our lifetime. But M.2 is a relatively new technology after all so it’s normal that some questions will arise. If you’re planning to use this new form factor, I’ve put together a list of the most commonly asked questions.
Just a quick note. The tests in this FAQ were done on the Plextor M6e PX-AG256M6e 256GB which comes with its own OPROM. There are a few drives out there that lack an OPROM so you might need to modify additional settings to make it bootable. Unfortunately, I do not own one of those drives so I can’t tell you what to change. But if I happened to get my hands on one later on, I’ll update this post."
Hit this forum thread to read on.