I seriously doubt Battlefield 4 will require more than 2GB. As has been mentioned, the extra VRAM will be used for caching textures and what not..Would be a cold day in hell if someone thinks i would swap my gtx770 for a 7970Ghz based on this apparent bs.
Honestly never thought to see so early a game push games at 1200p without AA to 2gb of vram usage,when i was in the market for a 4gb gtx760 originally with my budget plenty of people said 4gb was a waste for 1200p and i think i made that thread about 2 weeks ago lol then suddenly i buy the 2gb gtx770 and there goes that theory with these BF4 graphs huh?
Before I upgraded to GTX 770 4GB SLI, I had overclocked GTX 580 SLI with 1.5GB of VRAM..
I was able to play Bioshock Infinite at max settings, and Crysis 3 at VHQ 2560x1440 on my overclocked 580s..
Bioshock Infinite will use 3GB of VRAM, and Crysis 3 will use over 2GB of VRAM on my GTX 770s..
However, it still played smooth for the most part on my GTX 580s with their 1.5GB of VRAM.
So basically what I'm saying is, that a lot of the extra VRAM games use is for cache, and not for rendering output.