Valve once imagined that every PC maker could have their own "Steam Machine," a PC game console running the company's Linux-based SteamOS. It took a decade for that dream to evolve into the company's own internally developed Steam Deck gaming handheld, but the original dream isn't dead.

The company's long said it plans to let other companies use SteamOS, too — and that means explicitly supporting the rival Asus ROG Ally gaming handheld, Valve designer Lawrence Yang now confirms to The Verge.

A few days ago, some spotted an intriguing line in Valve's latest SteamOS release notes: “Added support for extra ROG Ally keys.” We didn't know Valve was supporting any ROG Ally keys at all, let alone extras!

Maybe Valve was just supporting those keys in the Steam desktop client on a Windows, where it offers a Steam Deck-like Big Picture Mode interface for any PC, and the line mistakenly made it into these patch notes? I asked to be safe.

But no: this is indeed about Valve eventually supporting the ROG Ally and other rival handhelds!

"The note about ROG Ally keys is related to third-party device support for SteamOS. The team is continuing to work on adding support for additional handhelds on SteamOS," Yang tells me.

That doesn't mean Asus will officially bless Valve's installer or sell the Ally with SteamOS, of course. (Asus has told me there are many reasons why it ships with Windows; a big one is that Microsoft has dedicated validation teams that ensure its operating system works across many different hardware configurations and chips.)

And it's not like Valve is suggesting it'll offer SteamOS for rival handhelds anytime soon, either. Valve is “making steady progress,” Yang tells me, but it “isn’t ready to run out of the box yet.”

We already knew Valve plans a general release of SteamOS 3 that you can theoretically install on non-handheld PCs as well; Yang says it's similarly making progress there but it's not ready quite yet.

So that's the update on turning Windows handhelds into Steam Machines; what about Valve's promise to let you turn Steam Decks into dual-booting Windows machines too, letting you swap between the two OS at will? Here's Yang on that:

As for Windows, we’re preparing to make the remaining Windows drivers for Steam Deck OLED available (you might have seen that we are prepping firmware for the Bluetooth driver). There’s no update on the timing for dual boot support—it’s still a priority, but we haven’t been able to get to it just yet.

Valve isn't the only one adapting its compelling combination of Linux and controller-friendly Steam UI to Windows handhelds. Universal Blue touted that its Bazzite operating system had already achieved support for the Asus ROG Ally X before it even came out.