Hello there @RB_Brendan!
Checking through the massive log, the main takeaway is that the path tracing shader compile process does complete, then crashes due a timeout. Yet, there are more than a few angles to consider:
[2026.01.23-22.06.12:413][809]LogD3D12RHI: Error: PageFault: PageFault at VA GPUAddress “0xFEFE000000” (GPU 0)
This specific error code points towards a handshake or memory access issue, which could be tied to either the drivers, or the GPU hardware itself.
[2026.01.23-22.05.09:006][807]LogStaticMesh: Warning: Invalid material [Air] used on Nanite static mesh [Sculpted_Site_GH_HotTub_Grass]. Only opaque or masked blend modes are currently supported, [BLEND_Translucent] blend mode was specified. (NOTE: “Disallow Nanite” on static mesh components can be used to suppress this warning and forcibly render the object as non-Nanite.)
[2026.01.23-22.05.09:048][807]LogStaticMesh: Warning: Invalid material [Flower_petal] used on Nanite static mesh [Salvia_nemorosa_004]. Only opaque or masked blend modes are currently supported, [BLEND_Translucent] blend mode was specified. (NOTE: “Disallow Nanite” on static mesh components can be used to suppress this warning and forcibly render the object as non-Nanite.)
There are multiple entries like this, close to a hundred, pointing at invalid material references on Nanite meshes using translucent blend modes.
[2026.01.23-22.03.26:623][ 0]LogScript: Warning: Attempted to access TRASH_InstancedStaticMeshComponent_48 via property proxySM, but TRASH_InstancedStaticMeshComponent_48 is not valid (pending kill or garbage)
This particular blueprint has several entries tied to invalid components and array conflicts.
[2026.01.23-22.05.09:494][809]LogD3D12RHI: Creating RTPSO with 135 shaders (126 cached, 9 new) took 12.51 ms. Compile time 9.82 ms, link time 2.65 ms.
[2026.01.23-22.05.24:466][809]LogD3D12RHI: Warning: GPU timeout: A payload (0x00000B66AA7A0000) on the [0x00000B61F1342800, Compute] queue has not completed after 5.000001 seconds.
[2026.01.23-22.05.24:474][809]LogD3D12RHI: Warning: GPU timeout: A payload (0x00000B678852E700) on the [0x00000B61F1342300, 3D] queue has not completed after 5.000001 seconds.
[2026.01.23-22.06.12:412][809]LogD3D12RHI: Error: GPU crash detected: Device 0 Removed: DXGI_ERROR_DEVICE_HUNG
And here’s the point where the compilation does complete, then the GPU hangs during execution, and the whole thing crashes. Now that we know all the points of conflict in the log, let’s try to fix them one by one:
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Use DDU to fully clear your drivers, then install the latest Studio drivers from nVidia, as these are the most stable for engine work
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Check all your assets using translucent materials with Nanite enabled, and either disable Naninte from them, or convert the materials to masked/opaque. A more nuclear approach would be to use no Nanite at all, setting up r.PathTracing.UseNanite 0
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Open any BPs tied to BP_ia_scatter_C and look for red error nodes, null references, and any other conflicts in the arrays. You could also disable it temporary and check the changes in the log
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Disable HAGS in Windows, as other cases in the community point it as a source of conflict. To do so, go to Windows Settings > System > Display > Graphics > Advanced graphics settings, and there, turn off “Hardware accelerated GPU scheduling”
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You mentioned setting up TdrDelay to 60, great approach, but please remember to set TdrDdiDelay to 60 as well, as it was not mentioned in your notes
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Optionally, you can test path tracing on a new, empty level, in order to rule out specific project issues
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Finally, after all these changes, please remember to repeat the cache clear (Deleted “Saved, Intermediate, & DerivedDataCache” folders then regenerated upon launch). After that, test your project again.
Hope this helps, and good luck!
