Oh and PS, AMD came up with the Displayport 1.3 standard(so we can get some 120hz 4k, single cable loving) and submitted that well, it was reported in October 2013 so either happened at that time or earlier and was then reported. We know that AMD have been going out of their way to try and get adaptive sync added to 1.2a to get it to consumers earlier... would they submit it at the same time or after submitting dp 1.3, or way before it? Answer is pretty obvious.
Again for the record, why are we going to get 120hz 4k screens which Asus amongst others have stated they will produce but are waiting on DP 1.3 to do it... AMD. Standards push us forwards. 4k was eventually made because there was no big push on from 1080p because there was no official standard, cable, nothing beyond 1080p. There were 2560x1600 screens and the like but these used tiling methods, there was no official standard to push the industry towards. 4k was the answer to that yet no one actually came up with a proper cabling standard for it... seemingly because everyone involved is stupid.