Can RTX 3090 Ti 24GB run gpt-oss-20b?

NVIDIA · 24 GB GDDR6X · 1008 GB/s bandwidth · OpenAI · 21.5B (active 3.6B) · MoE · model ctx up to 128K

Yes — the RTX 3090 Ti 24GB (24 GB GDDR6X) can run gpt-oss-20b. At Q4 with the default 8K context it needs ≈ 13.55 GB VRAM (weights 11.83 GB + KV cache 0.72 GB + 1 GB runtime overhead), which fits within 24 GB. Decode at Q4/8K: ≈ 178.2 tok/s (estimated, batch 1). FP16 needs ≈ 44.72 GB — does not fit on this card. Estimates come from memory-bandwidth math; rows tagged measured override estimates. Relative ranking is more reliable than absolute tok/s. Methodology.

Fit & speed by quant and context

Quant	Context	VRAM needed	Fits?	tok/s (decode)
Q4	4K	13.19 GB	Yes	178.2 est.
Q4	8K default	13.55 GB	Yes	178.2 est.
Q4	32K	15.71 GB	Yes	178.2 est.
FP16	4K	44.36 GB	No	41.0 est.
FP16	8K default	44.72 GB	No	40.3 est.
FP16	32K	46.88 GB	No	36.7 est.

Fits = weights + KV(ctx) + 1 GB overhead ≤ 95% of VRAM. Measured anchors are context-agnostic; the fit verdict is recomputed per context. A missing tok/s means the model is far beyond this card (offload-only territory).

VRAM breakdown at 8K context

Quant	Weights	KV cache	Overhead	Total needed	RTX 3090 Ti 24GB VRAM
Q4	11.83 GB	0.72 GB	1 GB	13.55 GB	24 GB
FP16	43.0 GB	0.72 GB	1 GB	44.72 GB	24 GB

Other GPUs that run gpt-oss-20b

• B200 192GB SXM — ≈1414.1 tok/s Q4 est.
• MI300X 192GB — ≈936.9 tok/s Q4 est.
• H200 141GB SXM5 — ≈848.5 tok/s Q4 est.
• H100 80GB SXM5 — ≈592.2 tok/s Q4 est.
• Gaudi 3 128GB — ≈579.1 tok/s Q4 est.
• A100 80GB SXM4 — ≈360.4 tok/s Q4 est.
• RTX 5090 32GB — ≈282.5 tok/s Q4 measured
• RTX 4090 24GB — ≈225.2 tok/s Q4 measured

All GPUs for gpt-oss-20b →

Other models for the RTX 3090 Ti 24GB

• Qwen3-0.6B — ≈801.8 tok/s Q4 est.
• gemma-3-1b-it — ≈641.5 tok/s Q4 est.
• Llama-3.2-1B-Instruct — ≈534.5 tok/s Q4 est.
• Qwen3-1.7B — ≈320.7 tok/s Q4 est.
• Qwen3-30B-A3B — ≈213.8 tok/s Q4 est.
• Qwen3-Coder-30B-A3B-Instruct — ≈213.8 tok/s Q4 est.
• GLM-4.7-Flash — ≈213.8 tok/s Q4 est.
• Qwen3-30B-A3B-Instruct-2507 — ≈213.8 tok/s Q4 est.

All models on the RTX 3090 Ti 24GB →