Today, Sony Interactive Entertainment confirmed that the PS5 will be backwards compatible with an "overwhelming majority" of PS4 games. In addition to this, PlayStation has also confirmed that the PS5 will run PS4 games "at a boosted frequency." In other words, the PS5 will run PS4 games better, which makes sense. According to Sony, this will result in games having a higher and more stable frame rate, and may even lead to the title having a higher resolution on PS5 compared to PS4.
"We're expecting backward compatible titles will run at a boosted frequency on PS5 so that they can benefit from higher or more stable frame rates and potentially higher resolutions," said Sony over on the PlayStation Blog. "We're currently evaluating games on a title-by-title basis to spot any issues that need adjustment from the original software developers."
Of course, a similar promise was made on the PS4 Pro, and even the Xbox Series X. And for the most part, this promise was upheld. However, some games have occasionally run worse on the PS4 Pro compared to the PS4. In other words, hopefully Sony is diligent in ensuring that developers don't cut corners on their ports.
"We have already tested hundreds of titles and are preparing to test thousands more as we move toward launch," said Sony. "We will provide updates on backward compatibility, along with much more PS5 news, in the months ahead."
What's interesting in this second quote is that there are more updates on backward compatibility to come. Could these updates include word of PS3, PS2, and PS1 backward compatibility support? Maybe, but right now it's not looking likely.
I’ve asked a few folks in the know about the PS1-PS3 rumors and while nobody could guarantee they weren’t true (most people aren’t briefed on every single detail of the console), they did all laugh at the idea. Seems like nonsense to me— Jason Schreier (@jasonschreier) March 18, 2020
The PlayStation 5 is currently scheduled to release sometime this holiday season. At the moment of publishing, it's unclear how much the console will launch, but we do have a growing list of every confirmed PS5 game.