# Alibaba Wan 2.1 1.3B / LTX-Video (Fast Consumer Video) VRAM Requirements & Hardware Sizing Guide

> **Quick Summary (Answer Capsule)**: Running Alibaba Wan 2.1 1.3B / LTX-Video (Fast Consumer Video) requires 6.53 GB at Q4_K_M (4-bit), 8.74 GB at Q8_0 (8-bit), and 12.88 GB at FP16. Recommended hardware sweet spot: Intel Arc B580 12GB. Scaling context past 32k tokens requires enabling FP8 KV-cache (-ctk q8_0) to prevent CUDA allocation failures.

## Memory Specifications by Precision
| Quantization Format | Precision Level | Required VRAM (8k context) | Quality Retention | Minimum Recommended GPU |
|---|---|---|---|---|
| 4-Bit (Q4_K_M) | Recommended Default | 6.53 GB | >98.2% Perplexity | Intel Arc B580 12GB |
| 8-Bit (Q8_0) | Near Lossless | 8.74 GB | ~99.9% Perplexity | Workstation / High-Tier GPU |
| 16-Bit (FP16/BF16) | Uncompressed Full | 12.88 GB | 100% Fidelity | Multi-GPU / Datacenter |

## Architectural Memory Analysis
Wan 2.1 1.3B is an efficient compact diffusion video transformer designed for rapid 480p standard-definition video generation. With 1.4B parameters, its 4-bit quantized weights occupy only ~1.8 GB, while temporal latent memory requires ~4.2 GB during generation, allowing 5-second video clips to render on budget 8GB–12GB GPUs.

## Tier 1 Free Software Optimization ($0)
Enable scaled dot-product attention via PyTorch 2.0+ and pass `--lowvram` mode. Clamping video duration to 81 frames keeps peak temporal memory inside 6.5 GB on 8GB graphics cards.

## 1-Click Launch Terminal Snippets
- Ollama: `ollama run wan-2-1-1-3b-480p:q4_K_M`
- vLLM: `vllm serve Alibaba / Lightricks/wan-2-1-1-3b-480p --max-model-len 8192 --gpu-memory-utilization 0.95`

## Verified Hardware & Cloud Pathways
- Amazon Hardware: [Intel Arc B580 12GB graphics card](https://www.amazon.com/s?k=Intel+Arc+B580+12GB+graphics+card&tag=sparecables-20) (rel="noopener sponsored")
- RunPod Cloud Rental: [Deploy Instance](https://runpod.io?ref=ynypzu94) (rel="noopener sponsored")
- Vast.ai Cloud Rental: [Deploy Instance](https://cloud.vast.ai/?ref_id=723130) (rel="noopener sponsored")

---
*Interactive Sizing Calculator available at: https://www.gpugarden.com/vram/wan-2-1-1-3b-480p/*