All the series 6 appear to be UHD 4K and not full 4K. Why gamers are not attracted to UHD or 4K... is the catch its only 30fps. With 1080p you should see 60 fps for the most part.
Check with Sony if they issued an update for 4K but gaming, I'd stick to 1080.
i just bought this samsung 6 series 4k tv, my issue is that it doesnt seem to be setting at 4k resolution. it just tells me 1920 by 1080 when i connect my ps4 with the hdmi cable.