RX 6800 / Windows 11 / Desktop 0.8.24 crashes on startup with exit code 3221225477 during torch.cuda.is_available()

Expected Behavior

ComfyUI Desktop should start normally and open the UI.

Actual Behavior

ComfyUI Desktop crashes at startup with:

Python process exited with code 3221225477 and signal null

This appears to happen during GPU probing. In my logs, the crash occurs when Python reaches torch.cuda.is_available().

Environment
GPU: AMD Radeon RX 6800 (16 GB VRAM)
Architecture: RDNA2 / gfx1030
OS: Windows 11
ComfyUI Desktop: v0.8.24
PyTorch: 2.9.1+rocmsdk20260116
HIP: 7.2.26024-f6f897bd3d
AMD Adrenalin driver: 26.1.1 (and 26.3.1)

Reproduction
Fresh install of ComfyUI Desktop on Windows.

On startup, Desktop crashes immediately and shows:
Python process exited with code 3221225477 and signal null

I also reproduced the failure directly outside ComfyUI with the bundled Python environment:

.\.venv\Scripts\python.exe -c "import torch; print(torch.__version__); print(torch.version.hip); print(torch.cuda.is_available())"

Output stops after:

2.9.1+rocmsdk20260116
7.2.26024-f6f897bd3d

The line for torch.cuda.is_available() is never printed because Python crashes at that point.

Additional Notes
This is a fresh install. ComfyUI has never successfully started on this machine.
Disabling extensions/plugins did not resolve the issue.
Logs suggest the crash is triggered during GPU detection, not during workflow execution.
The Windows exit code 3221225477 suggests a native access violation / hard crash rather than a Python exception.
What I already tested
Fresh install
Updated GPU driver
Disabling optional components/plugins
Direct PyTorch test outside the UI
Logs / Evidence

Relevant behavior:
Desktop crashes immediately at startup
The same crash happens when calling torch.cuda.is_available() manually
Exit code is consistently 3221225477

I can provide the full logs if needed.

Question
Is this a known issue with:

AMD RX 6800 / RDNA2 on Windows Desktop
the current ROCm/PyTorch bundle
or driver compatibility with ComfyUI Desktop 0.8.24?

Any recommended workaround would be appreciated.