From the Pixel Deck Facebook group which is my go to for Steam Deck game settings
*WITCHER 3: ENHANCED EDITION* (STEAM OS)
System Update Channel: Stable
Proton Version: Proton 7.0-5
Approximate Battery Life: 1.5 - 2 hrs
Frame Rate: 40 frames per second (fps)
UMA Buffer: 4 GB
SWAP FILE: 16 GB
SWAPPINESS: 50
**IMPORTANT**
On the GOG launcher screen change from DirectX 12 to DirectX 11
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Note: Pay attention to our brightness setting. This setting will give you a much more vivid and bright picture, especially at night. If you are using Decky Deck, we have our "Vibrant Deck" setting at 145.
*MAKE SURE YOU RESTART THE GAME AFTER ADJUSTING THE SEETINGS.*
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IMPORTANT: If you use photo mode you will want to set the vignette setting to “on.” If it’s off the screen will go black when trying to engage photo mode, apparently. We are not sure if this happens to everyone but it is a known issue. If you do not use photo mode, you can leave it set to “off.”
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Pixel Deck’s next settings release is The Witcher 3: Enhanced Edition! We’re very excited to bring you the very best of what game-play can look like on the Steam Deck. This game has a “Verified” Steam Deck compatibility rating on Steam (Steam OS).
We have been hard at work testing these settings thoroughly to ensure this game is presented on the Steam Deck with the highest possible frame-rate while maintaining the greatest possible graphical fidelity.
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UMA Buffer change tutorial:
https://www.facebook.com/pixeldeckgaming/videos/1230564550815760/
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Swapfile Tutorial:
https://www.youtube.com/watch?v=od9_a1QQQns&t=25s
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This next-gen update to one of the greatest RPG's ever made is absolutely amazing, albeit on the Steam Deck, presented some issues that needed to be ironed out. CD Projekt added so much new foliage to the game that our initial settings regarding foliage density and draw distance proved to be troublesome. We have set those to low to balance the performance and there is still more foliage at these low settings than on the original release (win win).
We have managed to get the game dialed in and running at 40 fps with some minor dips here and there, but nothing to write home about. These minor dips may occur in larger cities or dense wooded areas with heavy weather effects, but if you turn your performance overlay off you will be hard pressed to even notice.
(Note) If you wanted to set your fps to 30, it will be pretty much locked, but it is not necessary as the 40 fps setting is pretty close to perfect.
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