Can the RTX 4070 Laptop 8 GB run HunyuanVideo (13B, original)?
Not entirely. Even Q4_K_M is 4.2 GB over 8 GB, so ComfyUI keeps part of it in system RAM.
The smallest sensible file, Q4_K_M (7.9 GB), needs about 12.2 GB - 4.2 GB more than RTX 4070 Laptop 8 GB 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.
Also try the FP8 file (13.2 GB) on this GPU. It does not fit entirely, but a current ComfyUI streams the overflow from RAM and native 8-bit files often beat a small GGUF that does fit. Dynamic VRAM →
01With more VRAM
With 20 GB you could run HunyuanVideo 13B at 8-bit or better (FP8, 13.2 GB) with no offloading.
What changes from the RTX 4070 Laptop 8 GB to the RTX 3090 24 GB →
02Every HunyuanVideo 13B file on 8 GB
| File | Size | Needed | On this card | Quality | Download |
|---|---|---|---|---|---|
| 16-bit SAFETENSORS · Comfy-Org | 25.6 GB | 29.9 GB | 21.9 GB too big | the original weights | Hugging Face → |
| FP8 SAFETENSORS · Kijai | 13.2 GB | 17.5 GB | 9.5 GB too big | practically identical to the original | Hugging Face → |
| Q8_0 GGUF · city96 | 14.0 GB | 18.3 GB | 10.3 GB too big | practically identical to the original | Hugging Face → |
| Q6_K GGUF · city96 | 11.0 GB | 15.3 GB | 7.3 GB too big | very close to the original | Hugging Face → |
| Q5_K_M GGUF · city96 | 9.4 GB | 13.7 GB | 5.7 GB too big | close; small differences in fine detail | Hugging Face → |
| Q4_K_M ← GGUF · city96 | 7.9 GB | 12.2 GB | 4.2 GB too big | good; some loss in fine detail and text | Hugging Face → |
| Q3_K_M GGUF · city96 | 6.2 GB | 10.5 GB | 2.5 GB too big | noticeable loss of detail | Hugging Face → |
“Needed” adds 3.5 GB of working memory for HunyuanVideo 13B and a 0.8 GB reserve. Sizes 2026-10-01.
03What to download
| Part | File | Folder | Size | |
|---|---|---|---|---|
| Model | hunyuan-video-t2v-720p-Q4_K_M.gguf Q4_K_M · city96/HunyuanVideo-gguf | models/unet | 7.9 GB | Download → |
| Text encoder | llava_llama3_fp8_scaled.safetensors LLaVA-Llama3 FP8 (scaled) · Comfy-Org/HunyuanVideo_repackaged | models/text_encoders | 9.1 GB | Download → |
| Text encoder | clip_l.safetensors CLIP-L · Comfy-Org/HunyuanVideo_repackaged | models/text_encoders | 0.2 GB | Download → |
| VAE | hunyuan_video_vae_bf16.safetensors HunyuanVideo VAE BF16 · Comfy-Org/HunyuanVideo_repackaged | models/vae | 0.5 GB | Download → |
| Total download · keep about the same free on disk | 17.7 GB | |||
Alternatives: LLaVA-Llama3 FP16 (16.1 GB). Only for some workflows: LLaVA-Llama3 vision (0.6 GB, I2V only). Sizes from Hugging Face, 2026-10-01.
04The text encoder
At 9.1 GB even the smallest LLaVA-LLaMA-3 8B + CLIP-L file is too big for 8 GB, so it runs from system RAM. That slows down reading the prompt, not the picture. Sizes: 16-bit 16.1 GB, FP8 9.1 GB (plus CLIP-L (0.25 GB)). Why the encoder does not count against VRAM →
05Measured and reported results
Nobody has sent measured numbers for this pair yet. If you run HunyuanVideo 13B on a RTX 4070 Laptop 8 GB, send your time per image and peak VRAM and it will appear here, credited.
06About the RTX 4070 Laptop 8 GB
The RTX 4070 Laptop 8 GB is an Ada Lovelace GPU with hardware FP8, so ComfyUI can compute Comfy-Org's FP8 files natively: small and fast. (Plain FP8 files use FP8 maths with the --fast fp8_matrix_mult option.) As a laptop GPU it runs at a lower power limit than desktop cards (35–115 W depending on the laptop). The memory verdicts are the same; speed depends heavily on how much power the laptop maker allows.
8 GB GDDR6 · 128-bit · Ada Lovelace · 35–115 W. Everything that runs on it →
07Questions
How much VRAM does HunyuanVideo 13B need?
Around 10.5 GB with the smallest file (Q3_K_M) and 17.5 GB with an 8-bit file (FP8). The full 16-bit file needs about 29.9 GB.
Which HunyuanVideo 13B file should I download for the RTX 4070 Laptop 8 GB?
Q4_K_M (7.9 GB) from city96/HunyuanVideo-gguf. Load it with Unet Loader (GGUF) from the ComfyUI-GGUF node pack.
FP8 or Q8_0 for HunyuanVideo 13B on the RTX 4070 Laptop 8 GB?
FP8 (13.2 GB): the RTX 4070 Laptop 8 GB computes it natively, while Q8_0 (14.0 GB) is unpacked on the fly.
How much do I need to download for HunyuanVideo 13B on the RTX 4070 Laptop 8 GB?
17.7 GB: hunyuan-video-t2v-720p-Q4_K_M.gguf, llava_llama3_fp8_scaled.safetensors, clip_l.safetensors, hunyuan_video_vae_bf16.safetensors.