NVIDIA RTX 3090 Ti

The RTX 3090 Ti was NVIDIA's flagship Ampere GPU, offering 24 GB of GDDR6X memory with 1008 GB/s bandwidth - the same VRAM capacity as the RTX 4090. In 2026, used prices around $800-1000 make it one of the best VRAM-per-dollar options for local AI inference, capable of running Llama 3.3 70B at Q3_K_M entirely in VRAM.

Quick verdict

The RTX 3090 Ti remains a legendary local AI card in 2026. 24 GB VRAM at 1 TB/s bandwidth for under $1000 is hard to beat. It runs 30B models at Q8_0 and 70B models at Q3_K_M - all in VRAM. The 450W TDP is brutal, and it lacks the 4th-gen Tensor cores of Ada, but for pure inference it still delivers.

Spec breakdown

• VRAM: 24 GB GDDR6X
• Memory bandwidth: 1008 GB/s (21 Gbps)
• TDP: 450 W (recommend 1000W+ PSU)
• PCIe: 4.0 ×16
• Architecture: Ampere GA102-350
• CUDA cores: 10,752
• Tensor cores: 336 (3rd gen)

Real-world AI inference

Model	Tokens/sec	Source
Qwen3-30B Q4_K_M	~14 tok/s	r/LocalLLaMA
Llama 3.3 70B Q3_K_M	~8 tok/s	r/LocalLLaMA
Mistral Small 3 Q5_K_M	~28 tok/s	Community
ComfyUI SDXL (1024×1024)	~12 s/image	Community

Best models that fit

• Q5_K_M: Mistral Small 3 - comfortable
• Q8_0: Qwen3-30B - fits entirely in VRAM at high quality
• Q3_K_M: Llama 3.3 70B - all in VRAM, ~24 GB
• Dual 3090 Ti: 70B at Q4_K_M across two cards

Cost vs cloud

At ~$900 used, this is the best VRAM-per-dollar option. $50/month API users break even in 18 months. For 70B model enthusiasts, it's priceless.

Where to buy

• eBay used: ~$800-1,000
• Amazon used/refurbished: Button above

Honest alternatives

• RTX 4090 used (~$1,300): Same VRAM, faster, lower TDP
• Used RTX 3090 (~$700): Same VRAM, slightly slower, $200 less
• Dual RTX 3090 (~$1,400): 48 GB total - runs anything

What the community says

"Picked up a 3090 Ti for $850. 24 GB VRAM handles 70B at Q3_K_M and 30B at Q8_0. It's power-hungry but nothing else gives this much VRAM for the price."

• u/ampere-king on r/LocalLLaMA, 134 upvotes