Well, that certainly didn't take long did it? Valve have already put up an update to Proton Hotfix, that works around the crashing issue in DirectX 12 in The Witcher 3 next-gen on Steam Deck.
Now it will work out of the box without the need for any workarounds. You can simply uncheck any forced compatibility option you had set on it, as Valve set it to Proton Hotfix by default now for the Steam Deck. You can also install Proton Hotfix yourself in your Steam Library, and set it on the game manually in the compatibility menu if you have any issues.
Just imagine if CD Projekt gave Valve a bit of early notice and testing on this, it could've worked right away.

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There's still numerous issues with the new update though across all platforms, with masses of complaints about it. CD Projekt have announced that they're looking into it. Hopefully it won't be too long before it gets properly stable once again. Nice that it was a free update but they really need to do some more QA testing before pushing things out.
Does anyone know how to enable raytracing and DLSS in the game? They were grayed out.
Quoting: mahagrDoes anyone know how to enable raytracing and DLSS in the game? They were grayed out.
Use:
PROTON_ENABLE_NVAPI=1 VKD3D_CONFIG=dxr11 %command%
But you really don't have to bother because it'll crash very quickly after enabling RT. And I've read that savegames that are saved with RT on will not load properly with it off.
Last edited by Ehvis on 15 December 2022 at 4:03 pm UTC

Quoting: EhvisAnd I've read that savegames that are saved with RT on will not load properly with it off.Why would they make the save format depend on a graphics option?
Quoting: mahagrI tried. It took forever to load into the game. It crashed after a minute of gameplay. I gave up. I will wait...
Does anyone know how to enable raytracing and DLSS in the game? They were grayed out.
It still crashes immediately for me on my desktop, even with Proton Hotfix enabled.
Edit: Wrong setting... Tried too many combinations
Last edited by Mohandevir on 15 December 2022 at 8:55 pm UTC
Quoting: EhvisThe most interesting observation was that the game uses d3d11on12 for the dx12 "port" of the game, something that microsoft says NOT to do for complex 3d software because it's not optimised at all an causes higher cpu loads. In that regard it's something similar to the RTX remix from Portal RTX that also converts the game to another API in order to make it possible to inject some RT into it. Not ideal. I'll be continuing some gameplay test tonight and see how the DX11 version runs and what the differences are.witcher 3 now uses dxr raytracing, it needs dx12, because there is no dx11 raytracing implementation, at least modern and useful one . maybe part of the rendering code is translation of dx11 to dx12 but it is necessary anyway and might work faster just because of lower dx12 overhead
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