Comment by andreime

That's incorrect, where did you pick it up?

You can install SteamOS on any machine, but AMD GPU are somewhat required if you're not up to major tinkering. Valve does not officially support NVIDIA gpus atm; they are working on it.

Here's a video from Linus Tech Tips on how to do this https://www.youtube.com/watch?v=tdR-bxvQKN8 .