ComfyUI > Nodes > ComfyUI-SageAttention3 > Attention: Sage 3 (Blackwell)

ComfyUI Node: Attention: Sage 3 (Blackwell)

Class Name

Sage3AttentionOnlySwitch

Category
attention/Sage3
Author
wallen (Account age: 378days)
Extension
ComfyUI-SageAttention3
Latest Updated
2026-01-13
Github Stars
0.02K

How to Install ComfyUI-SageAttention3

Install this extension via the ComfyUI Manager by searching for ComfyUI-SageAttention3
  • 1. Click the Manager button in the main menu
  • 2. Select Custom Nodes Manager button
  • 3. Enter ComfyUI-SageAttention3 in the search bar
After installation, click the Restart button to restart ComfyUI. Then, manually refresh your browser to clear the cache and access the updated list of nodes.

Visit ComfyUI Online for ready-to-use ComfyUI environment

  • Free trial available
  • 16GB VRAM to 80GB VRAM GPU machines
  • 400+ preloaded models/nodes
  • Freedom to upload custom models/nodes
  • 200+ ready-to-run workflows
  • 100% private workspace with up to 200GB storage
  • Dedicated Support

Run ComfyUI Online

Attention: Sage 3 (Blackwell) Description

Enables exclusive Sage3 attention backend for efficient model performance and flexibility.

Attention: Sage 3 (Blackwell):

The Sage3AttentionOnlySwitch node is designed to provide a strict attention backend using the Sage3 library, specifically the sageattn3.api.sageattn3_blackwell module. This node is particularly useful for those who want to leverage the advanced capabilities of the Sage3 attention mechanism, which is known for its efficiency and performance in handling attention tasks. By integrating this node, you can ensure that your model utilizes the Sage3 attention backend exclusively, which can lead to improved computational efficiency and potentially better model performance. The node allows you to easily switch between enabling and disabling the Sage3 attention, providing flexibility in experimentation and deployment. Additionally, it offers the option to print the active backend, helping you keep track of which attention mechanism is currently in use.

Attention: Sage 3 (Blackwell) Input Parameters:

model

This parameter represents the model to which the Sage3 attention backend will be applied. It is crucial as it determines the context in which the Sage3 attention mechanism will operate. The model should be compatible with the Sage3 attention backend for optimal performance.

enable

This boolean parameter controls whether the Sage3 attention backend is enabled or not. When set to True, the Sage3 attention mechanism is activated, allowing the model to utilize its capabilities. If set to False, the node will revert to the default attention mechanism, typically torch.sdpa. The default value is True.

This boolean parameter determines whether the active backend should be printed to the console. It is useful for debugging and verification purposes, allowing you to confirm that the Sage3 attention backend is being used. The default value is True, and it provides a helpful message indicating the current backend in use.

Attention: Sage 3 (Blackwell) Output Parameters:

model

The output parameter is the model with the Sage3 attention backend applied if enabled. This output is crucial as it represents the modified model that now incorporates the Sage3 attention mechanism, potentially enhancing its performance and efficiency in attention-related tasks.

Attention: Sage 3 (Blackwell) Usage Tips:

  • Ensure that the sageattn3 library is installed in your environment by running pip install sageattn3 to avoid runtime errors.
  • Use the print_backend option to verify that the Sage3 attention backend is active, especially when troubleshooting or optimizing your model's performance.

Attention: Sage 3 (Blackwell) Common Errors and Solutions:

Sage3 (sageattn3) is not available

  • Explanation: This error occurs when the sageattn3 library is not installed or not accessible in your environment.
  • Solution: Install the sageattn3 library using the command pip install sageattn3 and ensure that your Python environment is correctly configured to access it.

Error running SageAttention3: <error_message>, falling back to pytorch attention.

  • Explanation: This error indicates that there was an issue executing the Sage3 attention mechanism, causing a fallback to the default PyTorch attention.
  • Solution: Check the error message for specific details, ensure that your model and inputs are compatible with Sage3, and verify that the sageattn3 library is correctly installed and configured.

Attention: Sage 3 (Blackwell) Related Nodes

Go back to the extension to check out more related nodes.
ComfyUI-SageAttention3
RunComfy
Copyright 2025 RunComfy. All Rights Reserved.

RunComfy is the premier ComfyUI platform, offering ComfyUI online environment and services, along with ComfyUI workflows featuring stunning visuals. RunComfy also provides AI Models, enabling artists to harness the latest AI tools to create incredible art.

Attention: Sage 3 (Blackwell)