the game crashes if i change the 3d api or set another resolution my fix was set the d3d api in "/home/deck/.local/share/Steam/userdata/45912693/257420/local/Serious Sam 4/UserCfg.lua" replace the contents with gfx_strAPI = "D3D11" sfx_strAPI = "OpenAL";

--then in game graphic settings you can now change the resolution to 1152x720 or 1024x576 --in performance change cpu gpu and memory to lowest --set fps in steam menu(...) to 50 fps, 10w tdp and gpu clock to 800 and activate fsr or nis the game runs smooth, you can get 60 fps if you increase tdp, gpu clock and fps