I tried to find the github issue, but it’s eluding me, so I’m going to go into detail since I spent about 3 weeks troubleshooting this.

Hard crash when playing a game. Restarts steam deck with a “verifying installation” message.

This happens anywhere from 2-15 minutes of playtime. Game didn’t matter, Terraria, Skyrim, Borderlands 1, Dave the Diver, Shredders Revenge, Doom 2016 … It was also reported by users with both LCD and OLED decks, so hardware revision didn’t matter either.

Anecdotally you find people saying that some of these steps work:

Memory retraining, re-imagining steam deck, Flashing different bios versions, Messing around with gpu clocks

But almost all of those threads loop back to the OP saying something like “nope, still crashing”. Any reprieve they did have seemed to be coincidental.

Valve themselves recommend those first two steps and then an RMA if it doesn’t fix it.

A Brazilian user in the issue tracker worked out you can flash BIOS 0116, and disable two specific memory power management flags. I believe the settings are hidden in other versions of the BIOS.

A Valve rep on the tracker confirmed that would work, but suggested not to do it as the deck is not functioning properly and needs to be replaced. They then closed the issue and advised to only use that fix if you can’t RMA.

Worth noting, 0116 is a pre-OLED BIOS, and can only be flashed to the LCD models. There is no way to reveal these BIOS flags on the OLED model, so you can only RMA in that case.

This has absolutely solved the problem. But I think I’m having a few dodgy side effects that weren’t happening before, like updates failing, and USB connection has become iffy and needing a few restarts to recognise devices are plugged in.

At least I can play games again, which work flawlessly now.