Local Video Generation
AI video generation is here — and it's the most demanding workload you can throw at consumer hardware. Heavy VRAM, long render times, and stunning results.
How it works
Video generation uses the same diffusion principles as image generation, but applied across many frames simultaneously. Instead of denoising a single image, the model denoises a 3D block of frames — a "video latent" — while maintaining temporal consistency so motion flows naturally.
This means VRAM requirements scale with both resolution and clip duration. A 5-second clip at 720p requires far more memory than a single image at the same resolution.
The models
| Model | Params | Min VRAM | Max resolution / duration | Notes |
|---|---|---|---|---|
| LTX-Video | 5B | 10 GB | 768×512, ~5 sec | Lightest, fastest — great starting point |
| Wan 2.1 | 14B | 16 GB | 832×480, ~5 sec | Strong motion quality, open license |
| HunyuanVideo | 13B | 24 GB | 1280×720, ~5 sec | Best open-source quality as of early 2025 |
| Cosmos | 7–14B | 16–24 GB | varies | NVIDIA's world-model series, physics-aware |
Tips for running video locally
- Use quantized versions of models (Q4/Q8) — they cut VRAM significantly with modest quality impact.
- Start with short clips (3–5 seconds) and lower resolution (480p) before attempting 720p or longer.
- Use ComfyUI for maximum flexibility — most video models have community workflows available.
- Keep system RAM high (32 GB+) — video models often page to RAM when VRAM is full during setup.
- Use NVIDIA's TensorRT compilation for ~2× faster rendering on supported models.
Running tools
Most video generation runs through ComfyUI with community workflow packs. A simpler GUI option is Wan Video GUI or dedicated launchers that wrap HunyuanVideo. No single "standard" GUI dominates the video space the way A1111 does for images — ComfyUI is the safe choice.
The RTX 5090's 32 GB VRAM is the consumer sweet spot for video generation — it runs HunyuanVideo and Wan 2.1 at 720p without aggressive quantization. The RTX 4090 (24 GB) handles these models with quantization applied. Cards below 16 GB are limited to LTX-Video and Wan 2.1 with heavy quantization at lower resolutions.
The DGX Spark's 128 GB unified memory removes most constraints — it runs HunyuanVideo at near-full precision, can handle longer clip durations, and makes batch generation practical. For production video workflows, Spark is the first desktop system that makes local video generation genuinely fast.