That might solve some of the problem if so. I'm not sure if they make DP > RCA adapters. I have the GPU hooked to the TV through a high speed HDMI cable (probably a mistake, but I have no alternative because there is no display port connector on the TV). Using a Power A Liquid Metal Wired Controller for Xbox One Come to find out after buying the TV and only seeing 60Hz as an option for a refresh rate, it only pushes 60Hz per channel in 3D mode equaling 120Hz only when both 3D channels are combined (which really isn't 120Hz still since each channel is only 60Hz, but whatever).
I'll start off by saying that I bought a 50' UHDTV that falsely advertised itself as 120Hz refresh. I know this is an old topic, but I just got the game and am having the same issue.