Advisor / Can it run? / gpt-oss 120B on RTX PRO 6000 96GB

Can RTX PRO 6000 96GB run gpt-oss 120B?

Measured results for gpt-oss 120B (116.83B MoE, 5.1B active) on RTX PRO 6000 96GB, plus what fits and the commands to run it.

260.8generation tok/s (Q8_0 on llama.cpp CUDA, 128-token generation)
9342prompt tok/s (pp512)
64.0 GBQ8_0 + 16k f16 KV, fits fully
95 GBusable on this hardware

Short answer

Yes. gpt-oss 120B Q8_0 fits fully on RTX PRO 6000 96GB at 16k context, using 64.0 of 95.0 GB usable, and generates about 260.8 tokens/s in our own run. As the context fills it slows down: 231.4 tok/s with 16k tokens already in context (89% of the empty-context speed), measured. For Q8_0, our bandwidth-only estimate was ~356 tok/s against a measured median of ~261 (37% too optimistic).

Measured generation speed by quantization

QuantGeneration tok/sRangePrompt tok/sRunsOrigin
Q8 class (median)260.8260.8–260.893421includes our runs
Q4 class (median)236.6196.3–276.972682includes our runs
Q4_K_M (our run, depth 0)276.93 repeats90173own measurement
Q8_0 (our run, depth 0)260.83 repeats93423own measurement

Generation = tg128 (128 generated tokens, short context). Public rows are medians of community llama.cpp results (sources); our own runs use llama-bench b11658 on a rented GPU.

Speed vs context depth measured

Our own llama-bench runs on RTX PRO 6000 Blackwell Workstation (flash attention on, 3 repeats): generation and prompt speed with the given number of tokens already in the context.

QuantContext depthGeneration tok/svs depth 0Prompt tok/s
Q4_K_M0276.9100%9017
Q4_K_M4k249.990%8761
Q4_K_M16k242.588%7708
Q8_00260.8100%9342
Q8_04k237.191%8968
Q8_016k231.489%7870

Alternatives

Less memory that still fits gpt-oss 120B

Smaller memory usually means a cheaper card or Mac (we do not list prices).

Other models on RTX PRO 6000 96GB, similar size

Memory and context limits

Q8_0 weights are 63.4 GB; the 16k f16 KV cache adds 0.61 GB. Largest context that fits in 95.0 GB usable:

KV cache typeMax context
f16128k
q8_0128k
q4_0128k

Native limit 128k. Full KV cache table for gpt-oss 120B.

Copy-paste commands

The advisor's pick for this hardware: Q8_0, 16k context.

llama.cpp
llama-server -hf unsloth/gpt-oss-120b-GGUF:Q8_0 -c 16384 -fa on --jinja -ngl 99
ollama
OLLAMA_CONTEXT_LENGTH=16384 ollama serve
ollama run hf.co/unsloth/gpt-oss-120b-GGUF:Q8_0

FAQ

How fast is gpt-oss 120B on RTX PRO 6000 96GB?

About 260.8 tokens/s for generation (Q8_0 on llama.cpp CUDA, 128-token generation), 9342 tokens/s for prompt processing. Speed drops as the context fills; see the depth table.

How much memory does gpt-oss 120B need on RTX PRO 6000 96GB?

The advisor's pick, Q8_0, is 63.4 GB of weights plus 0.61 GB of KV cache at 16k context (64.0 GB), against 95.0 GB usable.

Is the gpt-oss 120B speed on RTX PRO 6000 96GB measured or estimated?

Measured: our own llama-bench run on a rented RTX PRO 6000 Blackwell Workstation, including runs with 4k to 16k tokens already in context.

What can I use instead of RTX PRO 6000 96GB for gpt-oss 120B?

With less memory, Mac Studio (2025) M3 Ultra 96GB (~92 tok/s), Mac Studio M5 Max 128GB (~107 tok/s), MacBook Pro 14/16 M5 Max 128GB (~107 tok/s) also fit it fully.

What is the maximum context for gpt-oss 120B on RTX PRO 6000 96GB?

With an f16 KV cache about 128k tokens, 128k with q8_0 and 128k with q4_0, bounded by the model's own limit.

Related

All models on RTX PRO 6000 96GB · gpt-oss 120B on all hardware · VRAM tier · all measured pages · leaderboard

Compare: 2x RTX 3090 (48GB total) vs RTX PRO 6000 96GB