The image provided by valve is made specifically for the steam deck and likely won’t even boot properly on another handheld. If you want to have a steamOS experience on another handheld, distributions like Chimera Linux exist that will do that for you, and as far as I’m aware, Chimera is working on specific support for things like the ally.

Did you get the new one from the same place as the old one? It’s possible you got a bad or fake card.

I can understand this. The deck still isn’t the most portable thing in the world, and it’s a far throw from what the GPD WIN was when it originally released. I’m hoping that after lots of iteration a company will start attempting to make a more pocketable PC handheld again, even if the specs aren’t the absolute best. The real issue on the table is dealing with heat and battery life in a small form factor, something I don’t think anyone has been able to nail down yet. The future of x86 translation on ARM is interesting, but it’s got quite a way to go.

You can do usb-c to usb-c and have the deck show up as an MTP device like a cell phone, but it requires changing a setting in the bios to enable dual role mode for the USB port and using a plugin, iirc it’s called DeckMTP or something similar.

That looks like pressure damage to the screen. Have you put it into a bag or the case where something may have been putting pressure on the screen?