why are you so fixed on getting 12gb of ram?
anything past 8gb is not worth the money, even for gaming..
unless you plan on doing photoshop or any other graphic intense application...
8gb running at 1866mhz is more then enough ram power... 2133mhz sees not much benefits...
i would suggest getting 1000 Watt PS, future proofing is always good.. higher end graphics card requires more power... PS is the number 1 important item to get...
get a PS that has removable cables is good, less clutter inside the case... like the Silverstone Strider Plus...