Home / Models / GPT-OSS 20B / NVIDIA RTX 4090 24 GB

Calculated memory fit · not a benchmark

Can GPT-OSS 20B run on NVIDIA RTX 4090 24 GB?

Yes. Calculated memory fit: GPT-OSS 20B can run entirely in this GPU’s usable VRAM at one or more supported quantizations.

Can it run?

Can it run?: Yes, full GPU fit (calculated estimate).
Full GPU fit?: Yes
Model: GPT-OSS 20B · 22B
GPU: NVIDIA RTX 4090 24 GB · 24 GB advertised

Memory calculation

Breakdown for Q4 at 8K context, batch size 1. Calculator v1.0.0.

Model weights	12.6 GB
KV cache	0.4 GB
Runtime reserve	1.1 GB
Safety margin	0.6 GB
Required (estimated)	14.7 GB
GPU usable VRAM	21.6 GB

Result: FITS IN VRAM

Quantization table

Quantization	2K	4K	8K	16K	32K	64K	128K
BF16	Offload	Offload	Offload	Offload	Offload	Offload	Offload
FP16	Offload	Offload	Offload	Offload	Offload	Offload	Offload
Q3	Fits	Fits	Fits	Fits	Fits	Fits	Fits
Q4	Fits	Fits	Fits	Fits	Fits	Fits	Fits
Q5	Fits	Fits	Fits	Fits	Fits	Fits	Limited context
Q6	Fits	Fits	Fits	Fits	Fits	Limited context	Limited context
Q8	Offload	Offload	Offload	Offload	Offload	Offload	Offload

What fits entirely in VRAM?

Q3 at 128K context
Q3 at 16K context
Q3 at 2K context
Q3 at 32K context
Q3 at 4K context
Q3 at 64K context
Q3 at 8K context
Q4 at 128K context
Q4 at 16K context
Q4 at 2K context
Q4 at 32K context
Q4 at 4K context

What requires RAM offload?

Offload is shown only when the model does not fully fit in usable VRAM but stays within the modeled offload allowance.

Available graphics cards

These SKUs use this GPU chip. Amazon CTAs appear only for EXACT/HIGH matches. Absence of a price does not change the compatibility result above.

Check price on Amazon

MSI

MSI GAMING GeForce RTX 4090 X TRIO 24G NVIDIA 24 GB GDDR6X

24 GB · Amazon EXACT

$3490.00

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ASUS

ASUS ROG -STRIX-RTX4090-O24G-WHITE NVIDIA GeForce RTX 4090 24 GB GDDR6X

24 GB · Amazon EXACT

$2799.99

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GIGABYTE

GIGABYTE AERO GeForce RTX 4090 OC 24G NVIDIA 24 GB GDDR6X

24 GB · Amazon EXACT

$2579.99

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GIGABYTE

GIGABYTE GAMING GeForce RTX 4090 OC 24G NVIDIA 24 GB GDDR6X

24 GB · Amazon EXACT

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ASUS

ASUS TUF Gaming TUF-RTX4090-O24G-GAMING NVIDIA GeForce RTX 4090 24 GB GDDR6X

24 GB · Amazon EXACT

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MSI

MSI SUPRIM GeForce RTX 4090 LIQUID X 24G NVIDIA 24 GB GDDR6X

24 GB · Amazon EXACT

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GIGABYTE

GIGABYTE AORUS XTREME AORUS GeForce RTX 4090 XTREME WATERFORCE 24G NVIDIA 24 GB GDDR6X

24 GB · Amazon EXACT

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GIGABYTE

GIGABYTE GeForce RTX 4090 WINDFORCE V2 24G NVIDIA 24 GB GDDR6X

24 GB · Amazon EXACT

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GIGABYTE

GIGABYTE AORUS GeForce RTX 4090 MASTER 24G NVIDIA 24 GB GDDR6X

24 GB · Amazon EXACT

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MSI

MSI GAMING GEFORCE RTX 4090 X SLIM 24G graphics card NVIDIA 24 GB GDDR6X

24 GB · Amazon EXACT

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GIGABYTE

GIGABYTE GeForce RTX 4090 WINDFORCE 24G NVIDIA 24 GB GDDR6X

24 GB · Amazon EXACT

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ASUS

ASUS ROG -STRIX-RTX4090-O24G-GAMING NVIDIA GeForce RTX 4090 24 GB GDDR6X

24 GB · Amazon unmatched

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MSI

MSI SUPRIM GeForce RTX 4090 X 24G NVIDIA 24 GB GDDR6X

24 GB · Amazon unmatched

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ASUS

ASUS TUF Gaming TUF-RTX4090-O24G-OG-GAMING NVIDIA GeForce RTX 4090 24 GB GDDR6X

24 GB · Amazon unmatched

Check availability

ASUS

ASUS ROG -STRIX-RTX4090-24G-GAMING NVIDIA GeForce RTX 4090 24 GB GDDR6X

24 GB · Amazon unmatched

Check availability

MSI

MSI VENTUS GeForce RTX 4090 3X E 24G OC NVIDIA 24 GB GDDR6X

24 GB · Amazon unmatched

Check availability

Sources

Model: official config openai/gpt-oss-20b (main). GPU/product specs: Icecat. Compatibility: RigForAI calculator v1.0.0 estimated VRAM · Q8 at 8K: CPU_RAM_OFFLOAD_REQUIRED. Amazon: affiliate commerce match, not a spec source.