Xbox planning lead Albert Penello spoke with Eurogamer at E3 2016 about the extra CPU and GPU power of Xbox One S. In the conversation, Penello reveals that the new 4k capable console have no capacity to boost original Xbox One games in terms of gameplay.
"When we made changes to the box for 4K we unlocked a little bit more processing power to enable HDR. That's it. It's exactly the same architecture as the existing one. To support HDR, we give people access to a little more CPU and GPU. That's it. It is so insignificant it is mind boggling it is being picked up." — Albert Penello
The website also asked Phil Spencer regarding this matter and, he also confirmed that Xbox One S will not make your Xbox One games any better.
"It was designed to play Xbox One games exactly the same way your existing Xbox One does. The one definitive feature that's different is HDR. So, with the increased HDMI capability, it has the ability to support high dynamic range. I will say - and I've been asked about this - and I'm not trying to dodge the question, you should expect it to play your games the same way an Xbox One does. We did not design this to play Xbox One games better than the original Xbox One console." — Phil Spencer
So why brag that the Xbox One S is powerful when it can't boost your gameplay?