Llama 3.3 70B is the benchmark other open models are measured against: excellent instruction following, drafting quality and general knowledge, with the broadest ecosystem support of any family. The price is hardware: ~40GB of weights at Q4 means a 48GB card or a dual-24GB rig. If your tasks are RAG-grounded Q&A, test a 27B first โ the 70B earns its silicon on nuanced writing and harder reasoning.
VRAM by quantization level
| Quant | Weights | Fits on |
|---|---|---|
| Q4_K_M | ~40โ43 GB | 48GB card, or 2ร24GB (layer split) |
| IQ2_M | ~22โ24 GB | single 24GB โ noticeable quality loss; a good 27B at Q4 is usually smarter |
| Q8_0 | ~70 GB | 80GB datacenter card |
Weights only โ add KV-cache (grows with context and concurrency) and ~1โ2GB runtime overhead. Formula and cache math in the VRAM guide.
Quick start
Dual-GPU: llama.cpp/Ollama split layers automatically; vLLM with tensor-parallel 2 is faster for serving. Do not plan around CPU offloading โ every 20% of the model on CPU roughly halves speed. On Macs, a 96GB+ Studio runs Q5 with big context, quietly, at ~7โ10 tok/s.
Expected performance
| Hardware | Generation speed |
|---|---|
| 2ร RTX 3090 (Q4, layer split) | ~13โ18 tok/s |
| RTX A6000 48GB (Q4) | ~12โ15 tok/s |
| A100/H100 80GB (Q4/Q8) | ~25โ40 tok/s |
| Mac Studio 96โ192GB (Q5) | ~7โ10 tok/s |
Indicative single-user figures (llama.cpp/Ollama class runtimes); multi-user serving via vLLM multiplies total throughput 10โ20ร through batching.
Tips & gotchas
- Budget the KV-cache: 128K context can add tens of GB โ quantize the cache to Q8 and size for your real context.
- Occasional 70B need? Rent an 80GB GPU by the hour instead of buying โ the utilization math rarely favors owning for occasional use.
- Free for almost all business use; custom terms โ have someone read it before productizing.
FAQ
Can I run Llama 3.3 70B on one RTX 4090?
Only at IQ2-class quants with real quality loss, or with painful CPU offload. The honest single-card tier is 48GB; on 24GB, run a strong 27B instead.
Is the Llama license OK for company use?
For internal use, almost always yes. It has custom terms (not Apache/MIT) โ review before shipping it inside a product.