Can the RTX 4070 12 GB run LTX-Video 13B (0.9.8)?
Not at full quality. The 16-bit and 8-bit files are too big for the RTX 4070 12 GB; the largest that fits is Q3_K_M (6.5 GB).
Q3_K_M (6.5 GB) fits with only 1.2 GB to spare (about 10.8 GB of 12 GB). Quality: noticeable loss of detail. For better quality, Q4_K_M (8.8 GB) also runs, with about 1.1 GB spilling into system RAM - a little slower, still practical.
Also try the FP8 file (15.7 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 →
01What to download
| Part | File | Folder | Size | |
|---|---|---|---|---|
| Model | LTXV-13B-0.9.8-dev-Q3_K_M.gguf Q3_K_M · QuantStack/LTXV-13B-0.9.8-dev-GGUF | models/unet | 6.5 GB | Download → |
| Text encoder | t5xxl_fp8_e4m3fn_scaled.safetensors T5-XXL FP8 (scaled) · comfyanonymous/flux_text_encoders | models/text_encoders | 5.2 GB | Download → |
| VAE | LTXV-13B-0.9.8-dev-VAE.safetensors LTXV 13B 0.9.8 VAE (standalone, QuantStack) · QuantStack/LTXV-13B-0.9.8-dev-GGUF | models/vae | 2.5 GB | Download → |
| Total download · keep about the same free on disk | 14.2 GB | |||
Alternatives: T5-XXL FP16 (9.8 GB). Sizes from Hugging Face, 2026-10-01.
02Every LTX-Video 13B file on 12 GB
| File | Size | Needed | On this card | Quality | Download |
|---|---|---|---|---|---|
| 16-bit SAFETENSORS · Lightricks | 28.6 GB | 32.9 GB | 20.9 GB too big | the original weights | Hugging Face → |
| FP8 SAFETENSORS · Lightricks | 15.7 GB | 20.0 GB | 8.0 GB too big | practically identical to the original | Hugging Face → |
| Q8_0 GGUF · QuantStack | 14.0 GB | 18.3 GB | 6.3 GB too big | practically identical to the original | Hugging Face → |
| Q6_K GGUF · QuantStack | 10.9 GB | 15.2 GB | 3.2 GB too big | very close to the original | Hugging Face → |
| Q5_K_M GGUF · QuantStack | 9.8 GB | 14.1 GB | 2.1 GB too big | close; small differences in fine detail | Hugging Face → |
| Q4_K_M GGUF · QuantStack | 8.8 GB | 13.1 GB | spills 1.1 GB | good; some loss in fine detail and text | Hugging Face → |
| Q3_K_M ← GGUF · QuantStack | 6.5 GB | 10.8 GB | fits · 1.2 GB spare | noticeable loss of detail | Hugging Face → |
| Q2_K GGUF · QuantStack | 4.7 GB | 9.0 GB | fits · 3.0 GB spare | heavy loss; a last resort | Hugging Face → |
“Needed” adds 3.5 GB of working memory for LTX-Video 13B 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 LTX-Video 13B on a RTX 4070 12 GB, send your time per image and peak VRAM and it will appear here, credited.
04With more VRAM
With 20 GB you could run LTX-Video 13B at 8-bit or better (FP8, 15.7 GB) with no offloading.
What changes from the RTX 4070 12 GB to the RTX 4070 Ti Super 16 GB → · What changes from the RTX 4070 12 GB to the RTX 3090 24 GB →
05About the RTX 4070 12 GB
The RTX 4070 12 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.)
12 GB GDDR6X · 192-bit · 504 GB/s · Ada Lovelace. Everything that runs on it →
06Questions
How much VRAM does LTX-Video 13B need?
Around 9.0 GB with the smallest file (Q2_K) and 20.0 GB with an 8-bit file (FP8). The full 16-bit file needs about 32.9 GB.
Which LTX-Video 13B file should I download for the RTX 4070 12 GB?
Q3_K_M (6.5 GB) from QuantStack/LTXV-13B-0.9.8-dev-GGUF. Load it with Unet Loader (GGUF) from the ComfyUI-GGUF node pack.
FP8 or Q8_0 for LTX-Video 13B on the RTX 4070 12 GB?
FP8 (15.7 GB): the RTX 4070 12 GB computes it natively, while Q8_0 (14.0 GB) is unpacked on the fly.
How much do I need to download for LTX-Video 13B on the RTX 4070 12 GB?
14.2 GB: LTXV-13B-0.9.8-dev-Q3_K_M.gguf, t5xxl_fp8_e4m3fn_scaled.safetensors, LTXV-13B-0.9.8-dev-VAE.safetensors.