Stable Diffusion 1.5 on 20 GB of VRAM
Download 16-bit (2.1 GB). With the model's working memory it needs about 3.3 GB, leaving 16.7 GB spare on 20 GB. Quality: the original weights.
01What to download
| Part | File | Folder | Size | |
|---|---|---|---|---|
| Checkpoint | v1-5-pruned-emaonly-fp16.safetensors 16-bit · Comfy-Org/stable-diffusion-v1-5-archive | models/checkpoints | 2.1 GB | Download → |
| Total download · keep about the same free on disk | 2.1 GB | |||
One file: the checkpoint already contains the text encoders and the VAE. Sizes read from Hugging Face (2026-09-25). “Download” links start the file directly; the file name links are the same files the official ComfyUI workflows use.
System RAM: 16 GB or more. ComfyUI keeps the model file, the text encoder and the VAE in system RAM and moves them to the GPU as needed. With this set of files that is about 2.1 GB, plus roughly 6 GB for Windows, ComfyUI and a browser: 8.1 GB in total. With less RAM it still runs, but Windows starts swapping to disk and loading gets very slow. calculated
02Every file, on 20 GB
| File | Size | Needed | On this card | Quality | Download |
|---|---|---|---|---|---|
| 16-bit ← SAFETENSORS · Comfy-Org | 2.1 GB | 3.3 GB | fits · 16.7 GB spare | the original weights | Hugging Face → |
Sizes from the Hugging Face file listing, read 2026-09-25. “Needed” = file + 0.8 GB working memory for this model + 0.8 GB kept free for the system. The 2.13 GB checkpoint also holds the text encoder and VAE; the UNet alone is about 1.7 GB at 16-bit.
03The text encoder
The text encoder is inside the checkpoint, so there is nothing extra to download.