BBrainOutput

Best GPU for Local LLMs

The single biggest factor in which models you can run locally is GPU memory. This guide ranks GPUs by what they unlock — not just raw speed — so you buy the right amount of VRAM for the models you actually need.

VRAM is the gatekeeper

A model only runs if it fits in usable memory. 12GB handles 7–8B models at 4-bit; 24GB opens 32B-class models; 48GB fits a 70B model on one board. Bandwidth then decides how fast tokens generate.

Budget tiers

Entry: RTX 3060 12GB for a first assistant. Value: a used RTX 3090 (24GB). Flagship consumer: RTX 4090 (24GB, fast). Pro single-board 70B: RTX 6000 Ada or A6000 (48GB).

When to go multi-GPU

Two 24GB cards pool to 48GB for capacity and parallelism, but per-card bandwidth still bounds single-model speed. For one large model fast, prefer a single bigger card; for many agents, pool.

Featured chips

Recommended models

  1. 1
    Qwen2.5 72BQwen · ~72B · 128K ctx · Qwen License

    A top-tier open model for coding and reasoning; a strong backbone for a private Business Command Center.

  2. 2
    Llama 3.1 70BLlama · ~70B · 128K ctx · Llama Community License

    The previous-generation flagship; still excellent. Prefer Llama 3.3 70B where available for similar footprint and better instruction following.

  3. 3
    Llama 3.3 70BLlama · ~70B · 128K ctx · Llama Community License

    A flagship open model with near-frontier quality for many business tasks. Full precision needs multi-GPU/datacenter; 4-bit opens it to high-end workstations.

  4. 4
    DeepSeek-R1 Distill Llama 70BDeepSeek · ~70B · 128K ctx · MIT

    The largest R1 distill, built on Llama 70B. The strongest locally-runnable reasoning option short of the full MoE; plan for high-end workstation or multi-GPU hardware.

  5. 5
    Mixtral 8x7B (MoE)Mistral · ~47B · 32K ctx · Apache-2.0

    Mixture-of-experts: total params are large but only a subset activate per token, so it serves quickly for its quality tier.

Recommended hardware

Frequently asked questions

How much VRAM do I need to run a local LLM?+

Budget ~6GB for a 7–8B model at 4-bit, ~20GB for a 32B model, and ~42GB for a 70B model. The 4-bit (Q4) figure is the practical number to plan around.

Is the RTX 4090 the best GPU for local AI?+

It's the best consumer card for speed at 24GB. For 70B models on one board you need a 48GB pro card; for budget, the RTX 3060 12GB or a used 3090 are strong value.

Related guides

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