ThinkComputers visited AMD at CES 2017 in Las Vegas and got to see a PC with the AMD Ryzen CPU and a Vega-based video card running Star Wars Battlefront at a 4K resolution with all graphcis settings maxed out. Bob Buskirk reports the Ryzen chip was a 8-core, 16-threaded model running at 3.4GHz and notes the system delivered a solid 60fps.
A bit more information was scored by Videocardz. They have photos of the graphics settings and report the framerate was capped at 60fps but dropped to 57fps from time to time. So we don't know the true performance but it seems to be in NVIDIA GeForce GTX Titan X territory.