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Can the RTX 5080 16 GB run Stable Diffusion 3.5 Large?

Yes. Q8_0 fits on the RTX 5080 16 GB with 4.9 GB to spare.

Image model · 8.1B16 GB GDDR7 · 256-bit · 960 GB/s · BlackwellData 2026-10-01
Runs well
Yes.

Take Q8_0 (8.8 GB). In use it comes to about 11.1 GB, with 4.9 GB left over on 16 GB.

Best fileQ8_0
File size8.8 GB
VRAM needed~11.1 GB
System RAM32 GB+
Memory map · RTX 5080 16 GB11.1 GB / 16 GB
08 GB16 GB
Weights Q8_0 · 8.8 GBWorking memory · 1.5 GBReserve · 0.8 GBFree · 4.9 GB

01What to download

PartFileFolderSize
Modelsd3.5_large-Q8_0.gguf
Q8_0 · city96/stable-diffusion-3.5-large-gguf
models/unet8.8 GBDownload →
Text encodert5xxl_fp8_e4m3fn.safetensors
T5-XXL FP8 · Comfy-Org/stable-diffusion-3.5-fp8
models/text_encoders4.9 GBDownload →
Text encoderclip_l.safetensors
CLIP-L · Comfy-Org/stable-diffusion-3.5-fp8
models/text_encoders0.2 GBDownload →
Text encoderclip_g.safetensors
CLIP-G · Comfy-Org/stable-diffusion-3.5-fp8
models/text_encoders1.4 GBDownload →
VAEdiffusion_pytorch_model.safetensors
SD 3.5 VAE (gated repo: log in and accept the licence first) · stabilityai/stable-diffusion-3.5-large
models/vae0.2 GBDownload →
Total download · keep about the same free on disk15.5 GB

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

02Every SD 3.5 Large file on 16 GB

FileSizeNeededOn this cardQualityDownload
16-bit
SAFETENSORS · stabilityai
16.5 GB18.8 GB2.8 GB too bigthe original weightsHugging Face →
Q8_0 ←
GGUF · city96
8.8 GB11.1 GBfits · 4.9 GB sparepractically identical to the originalHugging Face →
Q5_1
GGUF · city96
6.3 GB8.6 GBfits · 7.4 GB spareclose; small differences in fine detailHugging Face →
Q4_1
GGUF · city96
5.3 GB7.6 GBfits · 8.4 GB sparegood; some loss in fine detail and textHugging Face →

“Needed” adds 1.5 GB of working memory for SD 3.5 Large 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 SD 3.5 Large 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 SD 3.5 Large need?

Around 7.6 GB with the smallest file (Q4_1) and 11.1 GB with an 8-bit file (Q8_0). The full 16-bit file needs about 18.8 GB.

Which SD 3.5 Large file should I download for the RTX 5080 16 GB?

Q8_0 (8.8 GB) from city96/stable-diffusion-3.5-large-gguf. Load it with Unet Loader (GGUF) from the ComfyUI-GGUF node pack.

How much do I need to download for SD 3.5 Large on the RTX 5080 16 GB?

15.5 GB: sd3.5_large-Q8_0.gguf, t5xxl_fp8_e4m3fn.safetensors, clip_l.safetensors, clip_g.safetensors, diffusion_pytorch_model.safetensors.