While you will undoubtedly need a 4K set to see the true benefits of Project Scorpio, you will get many enhances textures, geometry, and effects on standard HD displays. These images show enhancements Scorpio can make to existing Xbox One titles by virtue of resolution bumps alone, without any additional tweaking and features that utilize Scorpio's monstrous specs.
Native 4K Uncompressed Screengrab
Xbox One
4k on Scorpio (Image is 1080p)
1080p Supersampled Scorpio
Xbox One 1080p
Scorpio 4k Upgraded (1080p Image)
This was all shown in a close doors event for developers & press it seems.
Plenty of image slider comparisons here:
http://www.windowscentral.com/how-project-scorpio-enhances-games-at-1080p
Precision lock this thread if old.