Battlefield 1 looks pretty good. To compare how it scales between its settings, DigitalFoundry took a short amount of video at 4K across all four, omnibus graphics settings: Low, Medium, High, and Ultra. These are, as should be expected for a high-end PC game, broken down into more specific categories, like lighting quality and texture filtering, but I can't blame them for not adding that many permutations to a single video. It would just be a mess.
The rendering itself doesn't change too much between settings to my eye. Higher quality settings draw more distant objects than lower ones, and increases range that level of detail falls off, too. About a third of the way into the video, they show a house from a moderate distance. The lowest quality version was almost completely devoid of shadowing and its windows would not even draw. The lighting then scaled up from there as the settings were moved progressively toward Ultra.
Image Credit: DigitalFoundry
While it's still Alpha-level code, a single GTX 1080 was getting between 50 and 60 FPS at 4K. This is a good range to be in for a G-Sync monitor, as the single-card machine doesn't need to deal with multi-GPU issues, like pacing and driver support.