OpenAI

Gpt Oss 120B

OpenAI·120B·Transformer·128K ctx·2026-08

Check on my hardwareAdd to compare →Ollama →Hugging Face →

Model size→Hardware requirement→Actual fit

Gpt Oss 120B needs ~66.2–78 GB of VRAM depending on quantization. The bar is what it needs; the marker is the card's VRAM. Speed figures below are planning estimates.

8 GB

RTX 4060 · 3060 Ti

66.2
8
Q4_K_M · Est. ~1 tok/sWon't run

12 GB

RTX 4070 · 3060 12G

66.2
12
Q4_K_M · Est. ~1 tok/sWon't run

16 GB

RTX 4080 · M-series 16G

66.2
16
Q4_K_M · Est. ~1 tok/sWon't run

24 GB

RTX 4090 · 3090

66.2
24
Q4_K_M · Est. ~1 tok/sWon't run

48 GB

A6000 · 2×24G

66.2
48
Q4_K_M · Est. ~5 tok/sSlow · CPU offload

02  — Quantizations

QuantFile sizeEst. VRAM
Q4_K_M65 GB66.2 GB
Q5_K_M76.8 GB78 GB

03  — Runtimes & use

llama.cpp · Ollama · LM Studio

General · Max intelligence

Memory and speed figures are planning estimates, not measured benchmarks. Memory includes a fixed allowance for KV cache and runtime overhead. Long-context prompts push VRAM use above the numbers shown here.