Google's cloud gaming platform, Stadia, will be able to deliver up to 4K HDR content at 60fps. But will all of those games — some of them having come out long ago — be able to put up as much as the servers are willing to put out? Will they be 4K60, too? The short answer is yes.
The long answer comes courtesy of a tweet from Phil Harrison, a vice president and general manager leading Stadia efforts at Google, in response to a question about this very topic.
Yes, all games at launch support 4K. We designed Stadia to enable 4K/60 (with appropriate TV and bandwidth). We want all games to play 4K/60 but sometimes for artistic reasons a game is 4K/30 so Stadia always streams at 4K/60 via 2x encode.
— Phil Harrison (@MrPhilHarrison) October 9, 2019
Pretty much all of the older titles that have been announced for the Stadia's launch have had 4K remasters at some point, so it's not really a question of if the content is there.
Rather, the bigger questions, it seems, is about frame rate: Harrison says that Stadia will always stream at 60fps when the bandwidth is available to do so. That will mean 30fps content will be double-encoded and that other framerates that aren't a factor of 60 (you never know if and when game devs will start experimenting with that stuff) will probably look off.