Can I Run GPT-OSS 20B on NVIDIA GeForce RTX 4070?

Name: LLM Configurator — GPU VRAM Checker
Author: LLM Configurator

Written by Jakub Rusinowski · Last updated August 15, 2026

Yes. GPT-OSS 20B needs 10.6 GB at MXFP4 and the NVIDIA GeForce RTX 4070 has 12 GB, leaving about 1.4 GB of headroom, at roughly 39 tok/s (estimated).

The numbers

Model	GPT-OSS 20B
Parameters	20B
Quantization	MXFP4
VRAM needed	10.6 GB
NVIDIA GeForce RTX 4070 VRAM	12 GB
Verdict	Runs
Estimated speed	~39 tok/s

What to do next

Nothing to change — run it at MXFP4. If you want more capability, check whether the next size up also fits.

Affiliate disclosure: Some links on this page are affiliate links — if you buy through them, LLM Configurator may earn a commission at no extra cost to you. As an Amazon Associate, LLM Configurator earns from qualifying purchases.

Running GPT-OSS 20B on this card:

NVIDIA GeForce RTX 4070 12GB

12 GB VRAM · 200 W board power

2026 prices are volatile — check the current listing.

Check price on Amazon

Buy vs. rent GPT-OSS 20B

Buy the GPU

~$599

NVIDIA GeForce RTX 4070 · MSRP

Rent by the hour

from $0.34/hr

RTX 4090 (24 GB) class

At 2 hrs/day, buying (~$599) beats renting at $0.34/hr after about 2.4 years.

Affiliate links — we may earn a commission if you sign up, at no extra cost to you.

RunPod $0.34/hr

Rent on RunPod →

Vast.ai $0.35/hr · typical low · varies

Rent on Vast.ai →

Cloud rates verified 2026-07 — estimates, and marketplace prices vary. Buying price is GPU MSRP only, not a full PC.

Other GPT-OSS sizes on the NVIDIA GeForce RTX 4070

GPT-oss 120B — does not fit (72.5 GB)

GPT-OSS 20B on nearby hardware

Intel Arc B570 (10 GB) — runs at a lower quant
NVIDIA GeForce RTX 5080 (16 GB) — runs

All GPT-OSS sizes on the NVIDIA GeForce RTX 4070 | VRAM calculator for GPT-OSS 20B | NVIDIA GeForce RTX 4070 GPU page | Check your hardware