HiDream-O1-Image on 6 GB of VRAM
The smallest sensible file, FP8 (8.1 GB), needs about 10.9 GB — 4.9 GB more than 6 GB GPU has. ComfyUI can still run it by streaming part of the model from system RAM. How much slower that is depends on your ComfyUI version, the file format and the PCIe link — see the note below.
On RTX 40 and RTX 50 GPUs take the FP8 file instead of Q8_0: same class, faster there. On older NVIDIA, AMD and Intel GPUs Q8_0 is the better 8-bit file.
Worth trying on NVIDIA GPUs: with an up-to-date ComfyUI, Dynamic VRAM (on by default for NVIDIA since March 2026) streams whatever does not fit from system RAM, and ComfyUI's own start-up message recommends native FP8/INT8 files over GGUF, saying they “will be faster even if they are larger than your memory”. So before settling for a heavily compressed GGUF, try the native FP8 file (8.1 GB). The file recommended above is the best one that fits entirely — the safe choice on older ComfyUI versions, AMD and Intel. Comfy blog: Dynamic VRAM →
01What to download
| Part | File | Folder | Size | |
|---|---|---|---|---|
| Checkpoint | hidream_o1_image_fp8_scaled.safetensors FP8 · Comfy-Org/HiDream-O1-Image | models/checkpoints | 8.1 GB | Download → |
| Total download · keep about the same free on disk | 8.1 GB | |||
One file: this model has no separate text encoder or 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 8.1 GB, plus roughly 6 GB for Windows, ComfyUI and a browser: 14.1 GB in total. With less RAM it still runs, but Windows starts swapping to disk and loading gets very slow. calculated
02Every file, on 6 GB
| File | Size | Needed | On this card | Quality | Download |
|---|---|---|---|---|---|
| 16-bit SAFETENSORS · Comfy-Org | 16.4 GB | 19.2 GB | 13.2 GB too big | the original weights | Hugging Face → |
| FP8 ← SAFETENSORS · Comfy-Org | 8.1 GB | 10.9 GB | 4.9 GB too big | practically identical to the original | Hugging Face → |
Sizes from the Hugging Face file listing, read 2026-09-25. “Needed” = file + 2 GB working memory for this model + 0.8 GB kept free for the system. The Comfy-Org files are complete checkpoints (loaded from the checkpoints folder); there is no separate text encoder or VAE to add. No GGUF version was found.
03The text encoder
This model has no separate text encoder: reading the prompt is built into the model itself, so its memory is already in the file sizes above.