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Can the RTX 5080 16 GB run FLUX.1 Fill [dev]?

Yes, but only just: Q8_0 leaves 0.7 GB free on the RTX 5080 16 GB.

Image model · 12B16 GB GDDR7 · 256-bit · 960 GB/s · BlackwellData 2026-10-01
Runs well
Yes, just.

Q8_0 (12.7 GB) fits with only 0.7 GB to spare (about 15.3 GB of 16 GB).

Best fileQ8_0
File size12.7 GB
VRAM needed~15.3 GB
System RAM32 GB+
Memory map · RTX 5080 16 GB15.3 GB / 16 GB
08 GB16 GB
Weights Q8_0 · 12.7 GBWorking memory · 1.8 GBReserve · 0.8 GBFree · 0.7 GB

01What to download

PartFileFolderSize
Modelflux1-fill-dev-Q8_0.gguf
Q8_0 · YarvixPA/FLUX.1-Fill-dev-GGUF
models/unet12.7 GBDownload →
Text encodert5xxl_fp8_e4m3fn.safetensors
T5-XXL FP8 · comfyanonymous/flux_text_encoders
models/text_encoders4.9 GBDownload →
Text encoderclip_l.safetensors
CLIP-L · comfyanonymous/flux_text_encoders
models/text_encoders0.2 GBDownload →
VAEae.safetensors
FLUX.1 VAE (ae) · Comfy-Org/Lumina_Image_2.0_Repackaged
models/vae0.3 GBDownload →
Total download · keep about the same free on disk18.2 GB

Alternatives: T5-XXL FP16 (9.8 GB). Sizes from Hugging Face, 2026-10-01.

02Every FLUX.1 Fill file on 16 GB

FileSizeNeededOn this cardQualityDownload
16-bit
SAFETENSORS · black-forest-labs
23.8 GB26.4 GB10.4 GB too bigthe original weightsHugging Face →
Q8_0 ←
GGUF · YarvixPA
12.7 GB15.3 GBfits · 0.7 GB sparepractically identical to the originalHugging Face →
Q6_K
GGUF · YarvixPA
9.9 GB12.5 GBfits · 3.5 GB sparevery close to the originalHugging Face →
Q5_K_S
GGUF · YarvixPA
8.3 GB10.9 GBfits · 5.1 GB spareclose; small differences in fine detailHugging Face →
Q4_K_S
GGUF · YarvixPA
6.8 GB9.4 GBfits · 6.6 GB sparegood; some loss in fine detail and textHugging Face →
Q3_K_S
GGUF · YarvixPA
5.2 GB7.8 GBfits · 8.2 GB sparenoticeable loss of detailHugging Face →

“Needed” adds 1.8 GB of working memory for FLUX.1 Fill and a 0.8 GB reserve. Sizes 2026-10-01.

03Measured and reported results

Nobody has sent measured numbers for this pair yet. If you run FLUX.1 Fill on a RTX 5080 16 GB, send your time per image and peak VRAM and it will appear here, credited.

04About the RTX 5080 16 GB

The RTX 5080 16 GB is a Blackwell GPU with FP8 and FP4 hardware: ComfyUI computes Comfy-Org's FP8 files natively here, and NVFP4 files (where a model offers them) are faster still.

16 GB GDDR7 · 256-bit · 960 GB/s · Blackwell. Everything that runs on it →

05Questions

How much VRAM does FLUX.1 Fill need?

Around 7.8 GB with the smallest file (Q3_K_S) and 15.3 GB with an 8-bit file (Q8_0). The full 16-bit file needs about 26.4 GB.

Which FLUX.1 Fill file should I download for the RTX 5080 16 GB?

Q8_0 (12.7 GB) from YarvixPA/FLUX.1-Fill-dev-GGUF. Load it with Unet Loader (GGUF) from the ComfyUI-GGUF node pack.

How much do I need to download for FLUX.1 Fill on the RTX 5080 16 GB?

18.2 GB: flux1-fill-dev-Q8_0.gguf, t5xxl_fp8_e4m3fn.safetensors, clip_l.safetensors, ae.safetensors.