Thousands of titles will be available through backwards compatibility at launch, and Microsoft has put in over 500,000 hours of work to ensure each game runs in their best possible state. Ultimately, this allows games to run at “higher and more steady framerates and rendering at their maximum resolution and visual quality.”
“Backward compatible titles also benefit from significant reductions in load times due to the massive leap in performance from our custom NVME SSD at the heart of the Xbox Velocity Architecture. “
There’s also a new feature called Auto HDR, which adds HRD enhancements to titles that only shipped with SDR in the past. Check out the difference it has on Subnautica and Fuzion Frenzy in the image below.
Increased framerates basically across the board is a pretty incredible feat. The below video shows the effect that it has on Fallout 4, a game that was plagued with technical issues including regular framerate dips. On the Xbox Series X, it runs at 60 FPS.