Many build their own PC. Nowadays there are quite many models of handhelds but most are plagued with at least one of these problems:
Too bulky
Low Performance
Poor Battery
Poor screen
I’m not sure a Steam Deck 2 or 3 or 4, etc… mini, with efficient battery will be launched some day.
With the SteamOS I was starting to think if maybe I should try to build my own handheld.
Assembling all the parts available out there, re-purposing discarded devices parts.
Is this some kind of stupid idea? Not looking for validation, I’m just looking to learn if others tried.
You can build one, but it’s going to be everything you don’t want.
Devices like that are only so compact and sleek because every component was built/picked exactly for that spot. They knew what had to fit around what.
A hobbyist building their own thing is stuck picking stuff up off the shelf. None of that will fit as tightly together as the steam deck.
This is it. They aren’t “built out of parts” but custom made on a PCB made exactly to fit into the space available.
Unless OP is capable of DIYing a mainboard PCB containing a CPU and GPU plus support circuitry and custom cooling, there is no way to get less bulky than commercial solutions. Especially not while wanting to surpass them on performance and battery life.