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A simple successful image does not validate a larger graph; the tested workflow is the meaningful unit of GPU requirements.
Choose a ComfyUI GPU for a specific workflow: models, resolution, batch size and additional processing nodes. The interface does not define one minimum card for every task. Generating a simple image does not establish capacity for a larger graph with upscaling, extra models or video processing.
Save the complete graph
Preserve the workflow along with model files and revisions, custom-node versions and the software environment. A graph file without its dependencies may not reproduce on another server. Record any external inputs needed by the control task and ensure they can be used in the pilot.
Keep a small known workflow separate from the target graph. The first checks the basic environment; the second tests the actual requirement. A failure introduced by an additional node should not automatically be attributed to the GPU model or to ComfyUI itself.
Identify memory consumers by stage
| Workflow part | What to record | Requirement to test |
|---|---|---|
| Main model | Exact file and representation | Weight placement |
| Text encoder | Model and device | Additional memory |
| Generation | Image size and batch | Working-data peak |
| Decoding | VAE configuration | A different stage’s peak |
| Extra nodes | Versions and order | More models and intermediates |
Observe the complete pass, not only model loading. A graph can pass sampling and fail later while decoding the result. Keep timestamps with memory observations so the peak is associated with the responsible stage.
Verify the supported environment
ComfyUI’s system requirements distinguish installation and hardware routes. Support for the base environment does not guarantee every third-party node works on every card. Check the relevant node’s dependencies and preserve its version when reporting a result.
Start with a cleanly described setup rather than a collection of undocumented extensions. Change one dependency at a time when diagnosing the graph. If precision, memory management or a node changes, repeat the control output and review usefulness alongside memory.
Compare first and repeated runs
Measure initial loading separately from a repeated pass with the environment ready. Then test a sequence of representative jobs, including the larger input or batch the task actually needs. Record errors, peak VRAM, RAM and complete time to a saved output.
The resulting profile should state the tested graph and its boundary, rather than a universal claim about the card. That supports a concrete pilot and helps an operations partner relate additional resources to an observed stage of the task.
Official references: github.com — ComfyUI, docs.comfy.org — system requirements.
Related guides: A GPU OCR pipeline for a 1,000-page PDF workload, ComfyUI offloading: when moving data to RAM helps.