I can see why you're buying 12gb given that 24gb max motherboard.. but holy crap dude you're seriously wasting money with that motherboard. Not to mention that video card to boot.
You can't be thinking to spend big now so you can upgrade it in years to come... that simply doesn't happen. In 2 years time that motherboard will be obsolete in terms of supported memory type (THE biggest bottleneck in upgrading when it comes to performance) and cpu socket. That motherboard ONLY supports up to DDR3 2200 and the top memory type is DDR3 2400 ... which has been out for almost a year now. Aka, it is not long before the DDR 2600->3200 comes out in the market (or maybe even DDR4..DD3 has been around for 4+ years now).
Same thing with the video card. Although that card is SERIOUSLY kickarse as it is...it's extreme overkill. All games are designed to run on mid-end tiers.
You're paying a ton of money there for an insignificant performance benefit imo.
If you want to spoil yourself you could put that money into components that really,really last a long time.
Aka, get yourself a freakin' huge flatscreen monitor...or upgrade your computer case to something ridiculously fancy.... or just for kicks get yourself a solid state hard drive (which does improve game performance nicely).
...or buy that awesome thrustmaster Warthog joystick.. or get the latest Track IR

(or both!)