This model does not work with native ComfyUI INT8, and will need to be converted with this tool.
Unless you already downloaded this model, I recommend finding a more recent INT8 quant from Silveroxides to avoid having to do this.
INT8 ConvRot checkpoints for use with https://github.com/BobJohnson24/ComfyUI-INT8-Fast Should be slightly faster than FP8 on 40-50 series cards. ~1.6x faster than BF16 on my 3090.