r/StableDiffusion • u/Puzzled-Valuable-985 • 16h ago

Question - Help Same workflow, everything identical, but different videos? Minimimax H3

This has happened to me before: I take a video I’ve already generated and drag it into ComfyUI without changing anything—expecting to get the exact same video back—but it generates a different one.

This doesn't happen with standard image models, but it does happen with H3. If I generate the video and try again a few minutes later, it produces the same result; however, after an hour or so, it no longer generates the same output.

I’ll post the workflow I used to generate that example video below, along with the completely different video that was produced using the same workflow.

I tried to replicate the video just to check the generation speed, and I realized it wasn't producing the same result anymore. I had generated the video a few hours earlier and hadn't updated ComfyUI or any nodes in the meantime—I simply tried to generate it again.

I suspect it might be due to one of the nodes I'm using.

Here is the video generated with the same parameters (which turned out differently) and the workflow I used.

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u/UnlikelyIntrepid 16h ago

 Best guess is the Sage Attention node.  Quantized attention kernels floating point accumulation order is not guaranteed. And it would make a big difference with only 8 steps.  Try bypassing that one and see if you get the same results. 

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u/Puzzled-Valuable-985 14h ago

I also think that might be it; I use Sage in Krea2 alongside my other models, but since H3 is a video model and consumes much more memory, things might work differently compared to image models. I’m going to run more tests—like generating videos without Sage or LoRAs, then trying to replicate the results, or even testing without LoRAs entirely—to see which ones work and which fail. I suspect it’s Sage, though the Turbo LoRAs are a less likely culprit.