Xbox One S is not explicitly designed to increase game performance, according to Microsoft0 Comments
There wasn't much surprise when Microsoft announced the Xbox One S, or what's essentially just a slimmed-down Xbox One with 4K and HDR support. Things got a little jumbled, however, when a report from The Coalition studio head Rod Fergusson seemed to imply that the Xbox One S provided Gears of War 4 not only with a higher resolution, but a higher frame rate as well.
As it turns out, what may be true for Gears 4 may not be true for other games — and it's safe to say that the Xbox One S was not explicitly designed for increased performance. This fact is reinforced by a statement from Microsoft given to GameSpot:
"We have the same SOC architecture as Xbox One today," a Microsoft representative said. "For games that want to take advantage of HDR, we gave developers access to a small amount of additional processing power."
Essentially, the extra power given is there primarily to drive HDR support as well as 4K support, and isn't specifically designed to increase a game's performance. This confusion seems to center largely around Gears of War 4, where the game's performance is tied to framerate. Speaking in an interview with Polygon, Fergusson explained that the game is able to dynamically change its resolution in order to keep to a desired framerate — and with the extra power needed for higher resolutions, the game is able to more readily accomodate higher frame rates.
At least, that's what it sounds like. Put simply, any performance increase gained from the extra processing power given to the Xbox One S would be negligible compared to the previous Xbox One. For a true increase in power, Xbox fans will have to wait for the Scorpio console to release later in 2017.
E3 2016: Xbox One S's Power Does Not Improve Game Performance, Microsoft Says, GameSpot