Guide · Local AI
Best GPU for local AI in 2026
Bottom line: Buy a used RTX 3090 (24GB) first if you can find one near fair value (~$950). Need more speed at same VRAM? Step up to a 4090. On a budget, 4070 Ti Super (16GB) or 3060 12GB for light models. Prefer quiet always-on? See Mac mini / Studio or Mac vs GPU.
Why VRAM beats pure FPS for local AI
Local LLMs, diffusion, and video models load weights into GPU memory. A slightly slower card with 24GB often beats a faster 12GB card for model size. That is why used 3090s stay popular years after launch.
VRAM tiers (what you can run)
- 12GB — 7B–13B quantized models, light image gen. Entry cards: 3060 12GB, 4070.
- 16GB — Comfortable mid-size models. 4070 Ti Super, 4080 / 4080 Super.
- 24GB — Best consumer sweet spot. 3090, 4090, 7900 XTX.
- 48GB+ — Workstation (A6000, 6000 Ada) for large models without heavy quantization.
Ranked picks (used market)
- NVIDIA GeForce RTX 3090 — 24GB · fair ~$950. Still the local-AI value king for 24GB VRAM. Runs Qwen/Gemma-class 27B models at practical speeds. Dual-card builds are common.
- NVIDIA GeForce RTX 4090 — 24GB · fair ~$1,800. Fastest common consumer card for local LLM inference and image/video gen. Same 24GB VRAM as 3090 with much higher compute.
- NVIDIA GeForce RTX 3080 10GB — 10GB · fair ~$420. 10GB limits larger local models. Fine for 7B–13B quantized and gaming. Prefer 3090 if buying primarily for AI.
- NVIDIA GeForce RTX 3080 12GB — 12GB · fair ~$480. 12GB is a middle ground for local AI — better than 10GB 3080, still short of 24GB 3090 for larger models.
- NVIDIA GeForce RTX 4070 — 12GB · fair ~$480. Efficient 12GB Ada card. Solid for lighter local AI and excellent for 1440p gaming; not ideal for large LLMs.
- NVIDIA GeForce RTX 4070 Ti Super — 16GB · fair ~$720. 16GB Ada sweet spot for mid-size local models and strong gaming. Often competes with used 3090 on AI value.
- NVIDIA GeForce RTX 4080 — 16GB · fair ~$900. 16GB high-end Ada. Strong inference and creative work; still less VRAM headroom than 3090/4090 for big models.
- NVIDIA GeForce RTX 4080 Super — 16GB · fair ~$950. Refreshed 4080 with better price/performance. 16GB for local AI mid-tier models.
Used 3090 vs new alternatives
When used 3090 prices spike past fair high, some buyers switch to new AMD 24GB cards or 16GB Ada cards with warranty. Compare total dollars and CUDA ecosystem needs before switching.
What about Macs?
Apple Silicon is a real local-AI option because of unified memory (not VRAM). A Mac mini with 24–32GB or a used high-RAM Mac Studio can load models that fight a 24GB GPU — usually at lower tokens/sec and without CUDA. We track fair prices under Macs for local AI and compare stacks in Mac vs GPU.
Buying checklist
- Confirm full model name (avoid laptop / mobile variants).
- Ask for photos of the card, ports, and fan condition.
- Prefer local meetup or returns-friendly sellers for $800+ cards.
- PSU: 3090/4090 need serious wattage and PCIe power cables.
- Cross-check our fair value page and eBay sold comps before bidding.