Like Chino mentioned the best you can get is 760 and if possible a 770.
As for the ram, don't get a quad channel kit as the MVIE is a dual channel mobo the chances of a quad channel kit working is very low.

If your machine is for actual music production and not playing around in rofloops, I'd go mac book pro. As for other pro audio hardware this is the best place -> http://www.gearslutz.com/board/

i would go for the formula or hero board, the extreeme is more aimed for just overclockers.
the formula board have bether sound then the extreeme have, have a look on the specs of them on the asus.com site.
the formula is coming out this month ( not shure when to each country tho ).
memory, go from 1600 to 2133mhz range and 16gig since your going to make music and gaming, and dual channel.
PSU from 750w to 850w and you have a headroom to get a extra card down the line ( on the 850w one ).
and if your not going to do enny hypertreading, i would look at the i5 so you could save a few there.
if your gona do overclocking i would look around for an aftermarket cooler.

You say you already have or that you already have decided on.

The extreme is a lovely board, but my first choice for a gaming rig would be between the formula (just ahead in my choice) and the hero.

The video card is quite simple wonder over to Anandtech and see what the different cards in your price range perform like. Navigate to the bench section and then select the 2013 vga's