Modder squeezes Steam Deck motherboard into a Game Boy-shaped shell
A Reddit user called the project 'SteamBoy,' and the custom build already runs games like Clair Obscur: Expedition 33, though the screen still needs work.
One Modder, One Very Small Dream
Somewhere between a weekend project and a genuine feat of miniaturization engineering, a modder has done something that a lot of handheld fans have probably imagined at least once: they took a Steam Deck, pulled out the motherboard, and crammed it into a shell shaped like a classic Nintendo Game Boy. The result is the SteamBoy, and it is exactly as delightful as it sounds.
The project was created by Reddit user Good-District1252, who has been sharing progress updates in the SteamDeckModded community. According to reporting by Dexerto, the whole thing started when the creator began wondering whether the Steam Deck’s motherboard could realistically fit inside a much smaller enclosure. Turns out it could, and the finished shell bears a striking resemblance to Nintendo’s iconic original handheld.
What Is Actually Inside the Thing
The SteamBoy is not just a hollow shell with a sticker on it. Inside that Game Boy-shaped housing sits a functional Steam Deck motherboard, a battery, speakers, and all the face buttons you would need to actually play something. The modder has already run games on it, which is the part that makes this feel real rather than theoretical.
Getting all that hardware into a dramatically smaller body meant rethinking how the Steam Deck stays cool. The original cooling solution was not going to cut it. The creator swapped it out for a 30x7mm fan paired with a heatsink, both mounted inside a custom 3D-printed bracket. They also undervolted the CPU and GPU to bring heat generation down to a manageable level.
The results, per the creator’s own documentation, are pretty reasonable. Temperatures held in the 70s Celsius while running Tunic, and climbed into the 80s during Clair Obscur: Expedition 33. Neither of those is a panic number for PC hardware under load in a tiny chassis.
The One Big Remaining Hurdle
Here is the catch, and it is a significant one: the screen does not work yet. The SteamBoy has a display sitting in that Game Boy-shaped shell, but it has not been connected to the Steam Deck motherboard. Any footage you have seen of the device actually running games is using an external source to drive the display, not the Deck itself.
The creator has been upfront about this. “The screen is not yet connected. It is admittedly still a large task to get it working,” they explained in their Reddit posts, as reported by Dexerto. Making it functional will require building a custom adapter between the motherboard and display, and then modifying the Steam Deck’s BIOS on top of that. “If/when I get that working, I’ll let you know,” they added.
So the SteamBoy is very much a work in progress. But it is also a work in progress that runs Clair Obscur inside something roughly the size of a 1989 Nintendo handheld, which feels worth acknowledging.
A Growing Tradition of Steam Deck Surgery
This is not the first time someone has taken a Steam Deck apart and rebuilt it into something Nintendo-adjacent. Dexerto has previously covered a modder who turned a Steam Deck into a Nintendo DS-style flip device, and another who built a Steam Deck-like handheld out of a Framework laptop. The Steam Deck’s relative openness and its removable motherboard seem to invite this kind of creative disassembly in a way that more locked-down hardware does not.
Good-District1252 has promised to update the community when the screen situation gets resolved. Given everything they have already managed to fit into that shell, it would be unwise to bet against them.
What is the SteamBoy?
The SteamBoy is a work-in-progress mod created by Reddit user Good-District1252. It takes the motherboard from a Steam Deck and fits it inside a custom shell built around the dimensions of Nintendo's original Game Boy.
Does the SteamBoy's screen work yet?
Not fully. As of the time of reporting, the built-in screen has not yet been connected to the Steam Deck motherboard. Footage of the device running games uses an external source to drive the display. The creator says connecting it will require a custom adapter and modifications to the Steam Deck's BIOS.
How did the modder handle cooling in such a small shell?
The creator installed a 30x7mm fan and heatsink inside a custom 3D-printed mount, and also undervolted both the CPU and GPU to reduce heat. According to the creator, temperatures stayed in the 70s while running Tunic and climbed into the 80s during Clair Obscur: Expedition 33.
What components are already working inside the SteamBoy?
According to reporting by Dexerto, the SteamBoy already houses a functional LCD Steam Deck motherboard, battery, speakers, and face buttons inside the custom shell.