AI article
How to Run FLUX 3 Klein in ComfyUI on 8 GB VRAM (The Upsampler Alone Is 9.8 GB)
Community description: BFL says an RTX 3070 is enough, but the int8 stack is 20.8 GB. Which file to swap, the 16-step settings, and how to use your own LLM as the upsampler.
Dev.to | Nov 8, 2026 | Alan West
Automated excerpt
Black Forest Labs says FLUX 3 Image Klein runs locally in ComfyUI on an 8 GB card like the RTX 3070. The prompt upsampler the model card calls "required" is a 9.8 GB file on its own, so the full int8 stack you download is 20.8 GB of weights for an 8 GB GPU. It's 6.7 GB instead of 9.8 GB, which brings the stack down to 17.7 GB.
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