Fail Loading Libraries on AMD 6900xt with win11 25H2

### Custom Node Testing

- [ ] I have tried disabling custom nodes and the issue persists (see [how to disable custom nodes](https://docs.comfy.org/troubleshooting/custom-node-issues#step-1%3A-test-with-all-custom-nodes-disabled) if you need help)

### Expected Behavior

Install ComfyUI desktop ,create a new instance and launch it on my Win11 25H2 PC which is consisted of 9800x3d, msi b650i and sapphire 6900xt, with AMD software: PRO Edition 26.6.2 and AMD chipset Drivers 8.05.04.516 installed.

### Actual Behavior

The installation of lastest comfyUI(0.27.0) was pretty much smooth, then everything went on automatically with creating instance: it identified my hardware and chose AMD GPU, downloaded what it needs, established environment, but the operation failed when loading library.
You can check the logs, the torch tries to find backend CUDA which is not existed on my PC.

### Steps to Reproduce

With my hardware and operating system, you can easily reproduce when you try creat new instances. I have tried several times, also reinstallation doesn't work even after removing all comfyUI programe files, including files in the AppData.

### Debug Logs

```powershell
Process exited with code 3221225477 / 0xC0000005 (memory access violation — usually a faulty or missing native library)

> C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\.venv\Scripts\python.exe -s ComfyUI\main.py --feature-flag show_signin_button=true --feature-flag enable_telemetry=true --enable-manager --extra-model-paths-config "C:\Users\***\AppData\Roaming\Comfy Desktop\shared_model_paths.yaml" --input-directory C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\input --output-directory C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\output

[INFO] setup plugin alembic.autogenerate.schemas
[INFO] setup plugin alembic.autogenerate.tables
[INFO] setup plugin alembic.autogenerate.types
[INFO] setup plugin alembic.autogenerate.constraints
[INFO] setup plugin alembic.autogenerate.defaults
[INFO] setup plugin alembic.autogenerate.comments
[INFO] Adding extra search path checkpoints E:\Comfy-Desktop\ComfyUI-Shared\models\checkpoints
[INFO] Adding extra search path classifiers E:\Comfy-Desktop\ComfyUI-Shared\models\classifiers
[INFO] Adding extra search path clip_vision E:\Comfy-Desktop\ComfyUI-Shared\models\clip_vision
[INFO] Adding extra search path configs E:\Comfy-Desktop\ComfyUI-Shared\models\configs
[INFO] Adding extra search path controlnet E:\Comfy-Desktop\ComfyUI-Shared\models\controlnet
[INFO] Adding extra search path controlnet E:\Comfy-Desktop\ComfyUI-Shared\models\t2i_adapter
[INFO] Adding extra search path diffusers E:\Comfy-Desktop\ComfyUI-Shared\models\diffusers
[INFO] Adding extra search path diffusion_models E:\Comfy-Desktop\ComfyUI-Shared\models\diffusion_models
[INFO] Adding extra search path embeddings E:\Comfy-Desktop\ComfyUI-Shared\models\embeddings
[INFO] Adding extra search path gligen E:\Comfy-Desktop\ComfyUI-Shared\models\gligen
[INFO] Adding extra search path hypernetworks E:\Comfy-Desktop\ComfyUI-Shared\models\hypernetworks
[INFO] Adding extra search path latent_upscale_models E:\Comfy-Desktop\ComfyUI-Shared\models\latent_upscale_models
[INFO] Adding extra search path loras E:\Comfy-Desktop\ComfyUI-Shared\models\loras
[INFO] Adding extra search path model_patches E:\Comfy-Desktop\ComfyUI-Shared\models\model_patches
[INFO] Adding extra search path audio_encoders E:\Comfy-Desktop\ComfyUI-Shared\models\audio_encoders
[INFO] Adding extra search path photomaker E:\Comfy-Desktop\ComfyUI-Shared\models\photomaker
[INFO] Adding extra search path style_models E:\Comfy-Desktop\ComfyUI-Shared\models\style_models
[INFO] Adding extra search path text_encoders E:\Comfy-Desktop\ComfyUI-Shared\models\text_encoders
[INFO] Adding extra search path upscale_models E:\Comfy-Desktop\ComfyUI-Shared\models\upscale_models
[INFO] Adding extra search path background_removal E:\Comfy-Desktop\ComfyUI-Shared\models\background_removal
[INFO] Adding extra search path frame_interpolation E:\Comfy-Desktop\ComfyUI-Shared\models\frame_interpolation
[INFO] Adding extra search path geometry_estimation E:\Comfy-Desktop\ComfyUI-Shared\models\geometry_estimation
[INFO] Adding extra search path optical_flow E:\Comfy-Desktop\ComfyUI-Shared\models\optical_flow
[INFO] Adding extra search path detection E:\Comfy-Desktop\ComfyUI-Shared\models\detection
[INFO] Adding extra search path vae E:\Comfy-Desktop\ComfyUI-Shared\models\vae
[INFO] Adding extra search path vae_approx E:\Comfy-Desktop\ComfyUI-Shared\models\vae_approx
[INFO] Adding extra search path clip E:\Comfy-Desktop\ComfyUI-Shared\models\clip
[INFO] Adding extra search path unet E:\Comfy-Desktop\ComfyUI-Shared\models\unet
[INFO] Adding extra search path checkpoints C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\checkpoints
[INFO] Adding extra search path classifiers C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\classifiers
[INFO] Adding extra search path clip_vision C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\clip_vision
[INFO] Adding extra search path configs C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\configs
[INFO] Adding extra search path controlnet C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\controlnet
[INFO] Adding extra search path controlnet C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\t2i_adapter
[INFO] Adding extra search path diffusers C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\diffusers
[INFO] Adding extra search path diffusion_models C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\diffusion_models
[INFO] Adding extra search path embeddings C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\embeddings
[INFO] Adding extra search path gligen C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\gligen
[INFO] Adding extra search path hypernetworks C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\hypernetworks
[INFO] Adding extra search path latent_upscale_models C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\latent_upscale_models
[INFO] Adding extra search path loras C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\loras
[INFO] Adding extra search path model_patches C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\model_patches
[INFO] Adding extra search path audio_encoders C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\audio_encoders
[INFO] Adding extra search path photomaker C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\photomaker
[INFO] Adding extra search path style_models C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\style_models
[INFO] Adding extra search path text_encoders C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\text_encoders
[INFO] Adding extra search path upscale_models C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\upscale_models
[INFO] Adding extra search path background_removal C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\background_removal
[INFO] Adding extra search path frame_interpolation C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\frame_interpolation
[INFO] Adding extra search path geometry_estimation C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\geometry_estimation
[INFO] Adding extra search path optical_flow C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\optical_flow
[INFO] Adding extra search path detection C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\detection
[INFO] Adding extra search path vae C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\vae
[INFO] Adding extra search path vae_approx C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\vae_approx
[INFO] Adding extra search path clip C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\clip
[INFO] Adding extra search path unet C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\models\unet
[INFO] Setting output directory to: C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\output
[INFO] Setting input directory to: C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Shared\input
[START] Security scan
[DONE] Security scan
** ComfyUI startup time: 2026-07-03 23:00:45.877
** Platform: Windows
** Python version: 3.12.12 (main, Feb 12 2026, 00:40:26) [MSC v.1944 64 bit (AMD64)]
** Python executable: C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\.venv\Scripts\python.exe
** ComfyUI Path: C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI
** ComfyUI Base Folder Path: C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI
** User directory: C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\user
** ComfyUI-Manager config path: C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\user\__manager\config.ini
** Log path: C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\user\comfyui.log
[ComfyUI-Manager] WARN: Unsafe - SSL verification bypass option is Enabled. (see C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\user\__manager\config.ini)
[INFO] [PRE] ComfyUI-Manager
[WARNING] failed to run offload-arch: binary not found.
Windows fatal exception: access violation

Stack (most recent call first):
File "C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\.venv\Lib\site-packages\torch\cuda\__init__.py", line 182 in is_available
File "C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\.venv\Lib\site-packages\comfy_kitchen\backends\cuda\__init__.py", line 1912 in _register
File "C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\.venv\Lib\site-packages\comfy_kitchen\backends\cuda\__init__.py", line 1923 in
File "", line 488 in _call_with_frames_removed
File "", line 999 in exec_module
File "", line 935 in _load_unlocked
File "", line 1331 in _find_and_load_unlocked
File "", line 1360 in _find_and_load
File "", line 488 in _call_with_frames_removed
File "", line 1415 in _handle_fromlist
File "C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\.venv\Lib\site-packages\comfy_kitchen\__init__.py", line 3 in
File "", line 488 in _call_with_frames_removed
File "", line 999 in exec_module
File "", line 935 in _load_unlocked
File "", line 1331 in _find_and_load_unlocked
File "", line 1360 in _find_and_load
File "C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\comfy\quant_ops.py", line 7 in
File "", line 488 in _call_with_frames_removed
File "", line 999 in exec_module
File "", line 935 in _load_unlocked
File "", line 1331 in _find_and_load_unlocked
File "", line 1360 in _find_and_load
File "C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\comfy\memory_management.py", line 8 in
File "", line 488 in _call_with_frames_removed
File "", line 999 in exec_module
File "", line 935 in _load_unlocked
File "", line 1331 in _find_and_load_unlocked
File "", line 1360 in _find_and_load
File "C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\comfy\utils.py", line 25 in
File "", line 488 in _call_with_frames_removed
File "", line 999 in exec_module
File "", line 935 in _load_unlocked
File "", line 1331 in _find_and_load_unlocked
File "", line 1360 in _find_and_load
File "C:\Users\***\AppData\Local\Comfy-Desktop\ComfyUI-Installs\ComfyUI\ComfyUI\main.py", line 225 in

P.S. I mosaicked my username with ***, ignore it.
```

### Other

_No response_

Start at comfy/memory_management.py and comfy/quant_ops.py, then inspect the logged import path through comfy_kitchen/backends/cuda/__init__.py and torch.cuda.is_available on Windows. Reproduce by creating a ComfyUI 0.27.0 instance on the listed AMD setup and capture the backend-selection failure. Done means the instance launches without the access violation and loads the appropriate available backend.

Written by the indexing model from the issue text.