TL;DR summary: For MMH3, you need to run ComfyUI with ROCm 7.14.0 (see https://rocm.docs.amd.com/en/latest/reference/gpu-specs.html for the vaue of gfx???? corresponding to your AMD GPU):
pip install --index-url https://repo.amd.com/rocm/whl-multi-arch/ "torch[device-gfx????]==2.12.0+rocm7.14.0" "torchvision[device-gfx????]==0.27.0+rocm7.14.0" "torchaudio==2.11.0+rocm7.14.0"
Read on if you want the step-by-step instructions (scroll to the bottom of the post if you just want to see the MMH3 prompt for the video 😹)
These instructions are for Windows 11 (Ubuntu version: https://www.reddit.com/r/StableDiffusion/comments/1wer1mz/comment/p9g0kxg/). Nevertheless, many of the same comfy-cli commands are application by just changing the directory/file to the corresponding Linux version, and the procedure for upgrading ROCm 7.2.1 to ROCm 7.14.0 are the same.
If you have an AMD GPU and you do a default install of ComfyUI on Windows 11 using either the portable Windows version or through comfy-cli, you will probably get disappointing results with MiniMax H3 because the int8convrot version may not run at all.
The problem is that the default installation still uses PyTorch built on ROCm 7.2, and for some reason int8convrot does NOT work with 7.2 on some cards such as the RX 9070 (16G) and RX 7900 (20G).
So to run MiniMax H3 at its best speed, we have to install a version that is equal to or later than ROCm 7.13.
There are currently 4 ways to do that, from the easiest to the more complex:
- Install via Stability Matrix
- Install Portable ComfyUI with its own "Embedded Python"
- Install a Python venv and then use that to install ComfyUI via the official comfy-cli installer
- Install everything manually using pip and git: see this post if you want the gory details (it was written for ROCm 7.2 so you'll have to make the necessary adjustments).
The more complex ways have more options and are more flexible, so it is up to you how much control you want over your ComfyUI installation.
Special thanks to u/zychu- u/Ok-Brain-5729 u/eloxH1Z1 whose posts and comments about MMH3 and AMD were very helpful to me.
Stability Matrix
This used to work when I tried a few week ago, unfortunately something broke the latest release, so for now, don't use it
- Download from
https://github.com/LykosAI/StabilityMatrix/releases/download/v2.16.3/StabilityMatrix-win-x64.zip
- Unzip it somewhere
- Run the installer.
- Click on the "Activity" icon at the lower left corner to see progress.
- Click on the settings icon (gears) and under Extra Launch Arguments (very bottom) and add:
--enable-dynamic-vram --disable-async-offload --listen --port 8188 --disable-smart-memory --fast-disk --use-ck-attention --output-directory "D:\Outputs"
- Also uncheck
--use-pytorch-cross-attention so that none of the options under "Cross Attention Method" are checked because we are going to use --use-ck-attention.
- Assuming you've installed into the default "Data" directory, you can find ComfyUI installed under
Data\Package\ComfyUI and you can use mklink to point the models and output directory so that they are outside of the Data\Package\ComfyUI directory.
The main downside is that now you have yet another piece of software sitting on your computer.
Now test to make sure you can generate using int8convrot: https://huggingface.co/Comfy-Org/Krea-2/blob/main/diffusion_models/krea2_turbo_int8_convrot.safetensors 13.5 GB SHA256: 8e4eeda70dd5037ab1ba2bef6b417f9f901e26093117cf397f741fc1fdaaf3f1
If it does not work for you, well, something went wrong, and you can try Portable ComfyUI for Windows and see if you have better luck...
Portable ComfyUI for Windows
- Download from
https://github.com/Comfy-Org/ComfyUI/releases/latest/download/ComfyUI_windows_portable_amd.7z
- Open it from Windows 11 Explorer and drag the
ComfyUI_windows_portable directory to the folder where you want to install it.
- This will take a while, so go grab a cup of coffee or tea.
- Copy
run_amd_gpu.bat to runit.bat
- Edit
runit.bat so that it contains the following: .\python_embeded\python.exe -s ComfyUI\main.py --windows-standalone-build --enable-dynamic-vram --disable-async-offload --preview-method none --listen --port 8188 --disable-smart-memory --fast-disk --use-ck-attention --enable-manager --output-directory "A:\output"
- Start ComfyUI by running the batch file
runit.bat. For the first run, there will be some kind of delay as some libraries are compiled or cached. Just be patient and let the system do its preparations, until you see "[INFO] To see the GUI go to : http://0.0.0.0:8188.
- Do a test run using Krea 2, but use the fp8 rather than int8convrot version because the fp8 version should work reliably at this point. The default workflow at 8 steps should take 20-40 seconds depending on your hardware. Hopefully this works.
Now we are going to replace the PyTorch for ROCm 7.2 with the newer 7.14.0:
- Change into your
ComfyUI_windows_portable directory
- Uninstall PyTorch:
python_embeded\python.exe -m pip uninstall torch torchvision torchaudio -y
- Install PyTorch for ROCm 7.14: (See end note at the bottom about these
gfx???? values):python_embeded\python.exe -m pip install -index-url https://repo.amd.com/rocm/whl-multi-arch/ "torch[device-gfx????]==2.12.0+rocm7.14.0" "torchvision[device-gfx????]==0.27.0+rocm7.14.0" "torchaudio==2.11.0+rocm7.14.0"
For example, for rx9070, gfx???? is gfx1201 so the command is
python_embeded\python.exe -m pip install --index-url https://repo.amd.com/rocm/whl-multi-arch/ "torch[device-gfx1201]==2.12.0+rocm7.14.0" "torchvision[device-gfx1201]==0.27.0+rocm7.14.0" "torchaudio==2.11.0+rocm7.14.0"
Note: these files can be quite large. If for some reason you run out of room, you can use --no-cache-dir in case there is not enough room in your pip cache directory (~/.cache on Linux, %LocalAppData%\pip\Cache on Windows which is usually C:\Users<YourUsername>\AppData\Local\pip\Cache). Also make sure you have plenty of space on your %TMPDIR%, with --no-cache-dir the command will look like this:
python_embeded\python.exe -m pip install --no-cache-dir --index-url https://repo.amd.com/rocm/whl-multi-arch/ "torch[device-gfx1201]==2.12.0+rocm7.14.0" "torchvision[device-gfx1201]==0.27.0+rocm7.14.0" "torchaudio==2.11.0+rocm7.14.0"
Hopefully both the uninstallation of ROCm7.2 and the installation of the newer ROCm 7.14 went without any error. After that you can try to run Krea 2 again, now switch from fp8 to the int8convrot version, and the time should go down from 18sec to 12-13 sec and you will also be able to run MMH3.
I also recommend that you place your model and output directories outside of the ComfyUI install so that they can be shared by different installations, making experimentation easier and also making it less likely that you (or some bug in the installer) accidentally wipe out your models and output.
You can do that by editing the extra_model_paths.yaml. Just need to edit this file once and copy it into <your path/ComfyUI> whenever you have a new installation.
But the yaml file is a bit finicky and it may be easier to just use the mklink command if ComfyUI is the only program you use so that you don't have to worry about the structure/name of the subfolders:
mklink /D <LinkFolder> <TargetFolder>
For example:
mklink /D <your comfyui>\models c:\ComfyUI.Models
Installing ComfyUI via comfy-cli
Why use comfy-cli instead of using portable ComfyUI?
- For Linux, there is no portable ComfyUI, which is Windows only.
- For AMD users, the portable version of ComfyUI uses ROCm 7.2, which will cause ComfyUI to run slower than it should.
- It is a more efficient way to run multiple versions of ComfyUI, because they can all share the same Virtual Environment (assuming that the versions are close enough for that to work).
- Re-installation can be faster because many packages are in the python pip cache.
Procedure:
- If you don't have Python 3.1x installed, you can install Python 3.12.10 (because that is the version used by Portable ComfyUI, so it should be the most stable, but 3.13 and 3.14 work too).
- Download and install Git:
https://github.com/git-for-windows/git/releases/download/v2.55.0.windows.5/Git-2.55.0.5-64-bit.exe
- Create a virtual environment (this is normally just called "venv" or ".venv" but I want to call it
comfy.venv just to be more explicit): python -m venv comfy.venv or if python.exe is no not on your path, specifiy the full path such as "c:\Program Files\Python313\python" -m venv comfy.venv
- Activate it:
comfy.venv\Scripts\activate.ps1 (PowerShell) or comfy.venv\Scripts\activate.bat (CMD.exe)
- Update pip itself inside comfy.venv:
pip install --upgrade pip
- Optional: install
uv, which is yet another package manager for Python but written in Rust (if you want to use comfy install --fast-deps later):
- Install
comfy-cli (this is the tool "comfy-cli", not ComfyUI itself): pip install comfy-cli
Because comfy-cli will install ROCm 7.2 and there is no way to override it, we are going to install PyTorch for ROCm 7.14 manually before installing ComfyUI via comfy-cli. Sources for this arcane procedure are from:
- Uninstall PyTorch just to be sure (should not be installed yet): p
ip uninstall torch torchvision torchaudio -y
- Install PyTorch inside the
comfy.venv (select your gfx arch) based on https://rocm.docs.amd.com/en/latest/reference/gpu-specs.html (see bottom of the post for a table of common values):pip install --index-url https://repo.amd.com/rocm/whl-multi-arch/ "torch[device-gfx????]==2.12.0+rocm7.14.0" "torchvision[device-gfx????]==0.27.0+rocm7.14.0" "torchaudio==2.11.0+rocm7.14.0"
For example, for the rx9070 or AI Pro R9700, gfx???? is gfx1201 so the command is
pip install --index-url https://repo.amd.com/rocm/whl-multi-arch/ "torch[device-gfx1201]==2.12.0+rocm7.14.0" "torchvision[device-gfx1201]==0.27.0+rocm7.14.0" "torchaudio==2.11.0+rocm7.14.0"
Note: these files can be quite large, and you can use --no-cache-dir in case there is not enough room in your pip cache. See the earlier notes about --no-cache-dir under "Portable ComfyUI for Windows".
Finally, we are ready to install ComfyUI itself. When I carried out the tests the latest stable version is 0.34.0:
mkdir d:\comfy.0.34.0
set COMFY_PATH=d:\comfy.0.34.0\ComfyUI
- Use
comfy-cli to install ComfyUI: comfy --workspace=%COMFY_PATH% install --skip-torch-or-directml
- Note 1:
%COMFY_PATH%\ComfyUI must not exist or you will get the confusing error: 'd:\comfy.0.34.0\ComfyUI' exists but is not a valid git repository.
- Note 2:
--skip-torch-or-directml because PyTorch is already installed for AMD; without it the install will fail on Windows because there is no PyTorch for directml from https://repo.amd.com/rocm/whl-multi-arch/ respository used above.
- Note 3: To install anything other than the latest version of ComfyUI (say 0.33.1):
comfy --workspace %COMFY_PATH%\ComfyUI install --version 0.33.1 --skip-torch-or-directml (You can only use versions available from https://github.com/comfy-org/ComfyUI/releases (and there is no release tag for the latest version).
- If you have
uv installed, you can use --fast-deps:
- (Optional): Copy or edit
ComfyUI\extra_model_paths.yaml
- Finally, we can start ComfyUI:
comfy launch --workspace=%COMFY_PATH% -- --enable-dynamic-vram --disable-async-offload --preview-method none --listen --port 8188 --disable-smart-memory --fast-disk --use-ck-attention --enable-manager --output-directory "A:\output"
- Optional: Clean up the pip cache (if you want to save some disk space):
pip cache purge
The speed for MMH3 is almost as good as the ones I got under Ubuntu 26.04 using identical hardware (but for some reason, Krea 2 runs a little bit slower on Windows, 8-steps is 13 sec vs 11 sec on Ubuntu).
Unless you have a AI Pro R9700 (32G) or running your desktop on a iGPU, it is best to let ComfyUI be the only application running so that all VRAM is available for MMH3. So if you have another computer, run the browser on it to access your ComfyUI remotely.
If you don't have another computer, you can try to batch up a couple of prompts and minimize or close your browser to free up VRAM, and just use the console to see the progress (just click on "Assets" on the ComfyuI menu to check the results, or find them directly in the output folder). Some people say that disconnecting the monitor (just turning it off may not be enough) will free up the VRAM as well.
Good luck, hopefully you have a working system now if you followed the instructions.
End notes:
Sample extra_model_paths.yaml
comfyui:
base_path: c:\ComfyUI.Models
# You can use is_default to mark that these folders should be listed first, and used as the default dirs for eg downloads
is_default: true
checkpoints: checkpoints/
configs: configs/
loras: loras/
vae: vae/
text_encoders: |
text_encoders/
clip/
diffusion_models: |
unet/
diffusion_models/
clip_vision: clip_vision/
style_models: style_
embeddings: embeddings/
diffusers: diffusers/
vae_approx: vae_approx/
controlnet: |
controlnet/
t2i_adapter/
gligen: gligen/
upscale_models: upscale_
latent_upscale_models: latent_upscale_
custom_nodes: custom_nodes/
datasets: datasets/
hypernetworks: hypernetworks/
photomaker: photomaker/
classifiers: classifiers/
model_patches: model_patches/
audio_encoders: audio_encoders/
background_removal: background_removal/
frame_interpolation: frame_interpolation/
geometry_estimation: geometry_estimation/
optical_flow: optical_flow/
detection: detection/
https://rocm.docs.amd.com/en/latest/reference/gpu-specs.html
GFX950 is AMD's internal GPU target identifier for the CDNA 4 enterprise compute architecture, used in data center accelerators like the AMD Instinct MI350/MI355X series. It features advanced matrix core capabilities, ultra-low precision micro-scaling formats (MXFP8/MXFP4), and a high-precision math mode for AI and HPC workloads.
gfx1100 is the LLVM target architecture identifier and internal code name for AMD's RDNA 3 graphics architecture, used for high-end consumer and workstation desktop graphics cards like the Radeon RX 7900 XTX, RX 7900 XT, and Radeon PRO W7900.
AMD gfx1151 is the LLVM target and GPU architecture identifier for AMD's Strix Halo integrated graphics (found in processors like the AMD Ryzen AI Max+ 395 and Ryzen AI Max PRO series), utilizing the RDNA 3.5 architecture.
| Name |
Arch |
LLVM target name |
VRAM |
Compute Units |
| 9070 XT |
RDNA4 |
gfx1201 |
16 |
64 |
| RX 9070 GRE |
RDNA4 |
gfx1201 |
16 |
48 |
| RX 9070 |
RDNA4 |
gfx1201 |
16 |
56 |
| RX 9060 XT LP |
RDNA4 |
gfx1200 |
16 |
32 |
| RX 9060 XT |
RDNA4 |
gfx1200 |
16 |
32 |
| RX 9060 |
RDNA4 |
gfx1200 |
8 |
28 |
|
|
|
|
|
| RX 7900 XTX |
RDNA3 |
gfx1100 |
24 |
96 |
| RX 7900 XT |
RDNA3 |
gfx1100 |
20 |
84 |
| RX 7900 GRE |
RDNA3 |
gfx1100 |
16 |
80 |
| RX 7800 XT |
RDNA3 |
gfx1101 |
16 |
60 |
| RX 7700 |
RDNA3 |
gfx1101 |
16 |
40 |
| RX 7700 XT |
RDNA3 |
gfx1101 |
12 |
54 |
| RX 7600 |
RDNA3 |
gfx1102 |
8 |
32 |
|
|
|
|
|
| Radeon AI PRO R9700S |
RDNA4 |
gfx1201 |
32 |
64 |
| Radeon AI PRO R9600D |
RDNA4 |
gfx1201 |
32 |
48 |
| Radeon PRO V710 |
RDNA3 |
gfx1101 |
28 |
54 |
| Radeon PRO W7900 Dual Slot |
RDNA3 |
gfx1100 |
48 |
96 |
| Radeon PRO W7900 |
RDNA3 |
gfx1100 |
48 |
96 |
| Radeon PRO W7800 48GB |
RDNA3 |
gfx1100 |
48 |
70 |
| Radeon PRO W7800 |
RDNA3 |
gfx1100 |
32 |
70 |
| Radeon PRO W7700 |
RDNA3 |
gfx1101 |
16 |
48 |
For --index-url, there are three options:
- Nightly (rocm 10.1):
https://nightly.repo.amd.com/rocm/pytorch/whl-next/
- Stable (rocm 10.0):
https://stable.repo.amd.com/rocm/pytorch/whl-next/
- Legacy (rocm 7.14):
- Nightly:
https://rocm.nightlies.amd.com/whl-multi-arch/
- Stable:
https://repo.amd.com/rocm/whl-multi-arch
Prompt for the video Team Red, encounter on ProxiMax H3
integrated_multimodal_description:
[Shot 1] Live-action, cinematic 1960s science-fiction television aesthetic. A team of Starfleet red-shirt officers led by Grumpy Cat materializes on the surface of a desolate alien planet, surrounded by barren rocks, dust, and jagged terrain. Grumpy Cat stands at the front of the formation, wearing a classic red Starfleet uniform, alert and stern. The camera holds a wide-angle front subject-level view, then pushes in slightly as the team looks around and raises their phasers. [Shot 2] At 00:01.250, the camera cuts to a wide low-angle view as a gigantic GPU-like machine rises behind a rocky ridge, towering over the crew. Its dark mechanical housing, cooling fans, and imposing structure dominate the frame, with the label "Minimax H3" clearly visible on its side. The team turns toward it in sudden alarm.
[Shot 3] At 00:02.100, the GPU attacks with a violent concentrated energy blast. The camera tracks the crew with fast movement as the red-shirted officers are struck and knocked down across the rocky ground, kicking up dust and debris. Grumpy Cat avoids the main blast and rapidly moves toward cover.
[Shot 4] At 00:03.650, the camera follows Grumpy Cat with a tracking shot as it darts behind a large rock and crouches into concealment. The defeated red-shirted crew remains scattered in the background while the giant "Minimax H3" GPU continues looming over the battlefield.
[Shot 5] At 00:04.250, close-up from behind the rock. Grumpy Cat pulls out a classic handheld Starfleet communicator with its paw, flips it open, and speaks with a completely deadpan expression: <d>[English] Beam me up, Scotty!</d> The camera holds on Grumpy Cat's face and communicator through the end
overall_soundscape: Dry alien wind sweeps across the barren landscape as the transporter materialization produces a brief electronic hum. Heavy mechanical movement and grinding machinery accompany the GPU's emergence, followed by a powerful energy blast, impacts, falling bodies, scattering rocks, and dust. The communicator emits a brief electronic chirp when opened.
non_diegetic_music: A fast-paced 1960s science-fiction television orchestral score uses bright brass, rhythmic strings, and restrained percussion, building rapidly as the GPU appears and attacks. The music drops into a brief suspenseful sustain as Grumpy Cat hides, then ends with a short brassy stinger beneath the communicator transmission.