willitrun·ai

Can GPT-OSS 120B run on B100 192GB?

YES — Runs Great

S93Excellent
Estimated from fit model

GPT-OSS 120B needs ~96.4 GB VRAM. B100 192GB has 192.0 GB. With Q4_K_M quantization, expect ~102 tok/s.

Runtime: llama.cppCapacity: RoomyBandwidth: HighStack: StandardBottleneck: Balanced
Share:

Operating mode

Choose the run profile you care about

Interactive favors responsiveness, while light API and scale-out lean harder on serving readiness. The fit stays the same, but the recommendation lens changes.

Current mode

Balanced

Balanced for general local use. Keeps the ranking neutral across personal and serving workflows.

Capabilities:

Select quantization to explore

Q4_K_M (Medium quality) 96.4 GB, 102.4 tok/s, Runs well
96.4 GB required192.0 GB available
50% VRAM used

Fit status

Runs well

Decode

102.4 tok/s

TTFT

1891 ms

Safe context

131K

Memory

96.4 GB / 192.0 GB

Memory breakdown

Weights71.4 GB
KV Cache4.9 GB
Runtime0.9 GB
Headroom19.2 GB

See how fast it feels

See how fast it feelsGPT-OSS 120B on B100 192GB
1st promptCold start — includes initialization
>Write a Python function to sort a list
Here's a Python function that sorts a list using quicksort: def quicksort(arr): if len(arr) <= 1: return arr pivot = arr[len(arr) // 2] left = [x for x in arr if x < pivot] middle = [x for x in arr if x == pivot] right = [x for x in arr if x > pivot] return quicksort(left) + middle + quicksort(right) # Example usage numbers = [3, 6, 8, 10, 1, 2, 1] print(quicksort(numbers)) # [1, 1, 2, 3, 6, 8, 10] The algorithm picks a pivot, partitions the list into smaller, equal, and larger elements, then recursively sorts each partition and concatenates the results.
2nd promptWarm — model ready, no init overhead
>Now add type hints and a docstring
def quicksort(arr: list[int]) -> list[int]: """Sort a list using the quicksort algorithm. Args: arr: List of integers to sort. Returns: A new sorted list. """ if len(arr) <= 1: return arr pivot = arr[len(arr) // 2] left = [x for x in arr if x < pivot] middle = [x for x in arr if x == pivot] right = [x for x in arr if x > pivot] return quicksort(left) + middle + quicksort(right) Added type hints for the input and return type, plus a Google-style docstring.
Estimated: 102.4 tok/s decode · 1.9s TTFT (warm) · 256 tok/s prefill

What limits this setup

This setup is broadly balanced for this model.

No major red flags

This recommendation has enough memory headroom and acceptable estimated speed for the selected workload.

Best improvement path

Performance by workload

WorkloadGradeFitDecodeTTFTContext
ChatSRuns well102.4 tok/s1031 ms131K
CodingSRuns well102.4 tok/s1891 ms131K
Agentic CodingSRuns well102.4 tok/s2750 ms131K
ReasoningSRuns well102.4 tok/s2234 ms131K
RAGSRuns well102.4 tok/s3438 ms131K

Inference speed

GPT-OSS 120B inference speed — tokens per second by GPU & Mac

Estimated decode speed (tokens/sec) for GPT-OSS 120B at Q4_K_M across popular GPUs and Apple Silicon, including multi-GPU rigs, using the fastest local runtime per device. Fastest is MacBook Pro M4 Max 128GB at ~9 tok/s. Speed is memory-bandwidth bound, so cards that fit the whole model in VRAM run far faster than ones that offload to system RAM.

GPU / MacMemoryQuantSpeed (tok/s)Fits?
MacBook Pro M4 Max 128GB
128 GBQ4_K_M9.2Offloads
Mac Studio M3 Ultra 256GB
256 GBQ4_K_M8.5Fits
Mac Studio M2 Ultra 128GB
128 GBQ4_K_M7.1Offloads
Mac Studio M1 Ultra 128GB
128 GBQ4_K_M6.7Offloads
2× RX 7900 XTX 24GB
48 GBQ4_K_M4.4Too big
MacBook Pro M4 Max 64GB
64 GBQ4_K_M4.3Too big
NVIDIA2× RTX 4090 24GB
48 GBQ4_K_M3.1Too big
MacBook Pro M4 Pro 48GB
48 GBQ4_K_M2.6Too big
NVIDIA2× RTX 3090 24GB
48 GBQ4_K_M2.6Too big
NVIDIA4× RTX 3060 12GB
48 GBQ4_K_M2.3Too big
NVIDIARTX 5090 32GB
32 GBQ4_K_M2.0Too big
NVIDIARTX 4090 24GB
24 GBQ4_K_M2.0Too big
NVIDIARTX 4080 Super 16GB
16 GBQ4_K_M2.0Too big
NVIDIARTX 3090 24GB
24 GBQ4_K_M2.0Too big
NVIDIARTX 4070 12GB
12 GBQ4_K_M2.0Too big
NVIDIARTX 3060 12GB
12 GBQ4_K_M2.0Too big
NVIDIARTX 4060 8GB
8 GBQ4_K_M2.0Too big
RX 7900 XTX 24GB
24 GBQ4_K_M2.0Too big
MacBook Pro M3 Max 64GB
64 GBQ4_K_M2.0Too big
MacBook Pro M1 Max 64GB
64 GBQ4_K_M2.0Too big

Estimates for single-stream decoding at Q4_K_M; real tokens/sec varies with prompt length, context, batch size, and runtime build. Prompt processing (prefill) is faster than the decode figures shown here.

Quantization options

How GPT-OSS 120B (117B params) fits at each quantization level on B100 192GB (192.0 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
45.6 GB
LowA81
Q3_K_S
3
57.3 GB
LowA83
NVFP4
4
65.5 GB
MediumA84
Q4_K_M
4
71.4 GB
MediumA84
Q5_K_M
5
84.2 GB
HighS86
Q6_K
6
95.9 GB
HighS87
Q8_0Best for your GPU
8
125.2 GB
Very HighS88
F16
16
239.8 GB
MaximumF0

Get started

Copy-paste commands to run GPT-OSS 120B on your machine.

Run

ollama run gpt-oss:120b

Your hardware

More models your B100 192GB can run

ModelParamsGradeDecodeCapabilities
MistralDevstral 2 123B Instruct123BS97.4 tok/s
AlibabaQwen 3.5 122B A10B122BS270.2 tok/s
DeepSeekDeepSeek V4 Flash284BS144.8 tok/s
MistralMistral Small 4 119B119BS292.9 tok/s

Frequently asked questions

Can B100 192GB run GPT-OSS 120B?

Yes, B100 192GB can run GPT-OSS 120B with a S grade (Runs well). Expected decode speed: 102.4 tok/s.

How much VRAM does GPT-OSS 120B need?

GPT-OSS 120B (117B parameters) requires approximately 96.4 GB of memory with Q4_K_M quantization.

What is the best quantization for GPT-OSS 120B?

The recommended quantization for GPT-OSS 120B is Q4_K_M, which balances quality and memory efficiency.

What speed will GPT-OSS 120B run at on B100 192GB?

On B100 192GB, GPT-OSS 120B achieves approximately 102.4 tokens per second decode speed with a time-to-first-token of 1891ms using Q4_K_M quantization.

Can B100 192GB run GPT-OSS 120B for coding?

For coding workloads, GPT-OSS 120B on B100 192GB receives a S grade with 102.4 tok/s and 131K context.

What context window can GPT-OSS 120B use on B100 192GB?

On B100 192GB, GPT-OSS 120B can safely use up to 131K tokens of context. The model's official context limit is 131K, but available memory constrains the safe maximum.

See all results for B100 192GBSee all hardware for GPT-OSS 120B
Embed this result

Paste this snippet into any page to show a live fit card.

<iframe src="https://willitrunai.com/embed/gpt-oss-120b-on-b100-192gb" width="400" height="180" frameborder="0" style="border:none;border-radius:12px;overflow:hidden;" title="Will It Run AI — fit result"></iframe>

Preview: