amd/gpt-oss-120b-w-mxfp4-a-fp8
Model Overview
- Model Architecture: gpt-oss-120b
- Input: Text
- Output: Text
- Supported Hardware Microarchitecture: AMD MI350/MI355
- ROCm: 7.0
- Operating System(s): Linux
- Inference Engine: vLLM
- Model Optimizer: AMD-Quark
- Weight quantization: OCP MXFP4, Static
- Activation quantization: OCP MXFP4, Dynamic
- Calibration Dataset: Pile
This model was built with gpt-oss-120b model by applying AMD-Quark for MXFP4 quantization.
Model Quantization
The model was quantized from openai/gpt-oss-120b using AMD-Quark. The weights are quantized MXFP4 and activations were quantized to FP8.
Quantization scripts:
cd Quark/examples/torch/language_modeling/llm_ptq/
exclude_layers="*lm_head *self_attn* *router*"
python3 internal_scripts/quantize_quark.py \
--model_dir openai/gpt-oss-120b \
--quant_scheme w_mxfp4_a_fp8 \
--exclude_layers $exclude_layers \
--num_calib_data 512 \
--output_dir amd/gpt-oss120b-w-mxfp4-a-fp8 \
--model_export hf_format \
--multi_gpuDeployment
Use with vLLM
This model can be deployed efficiently using the vLLM backend.
Evaluation
The model was evaluated on AIME25 and GPQA Diamond benchmarks with low reasoning effort.
Accuracy
<table> <tr> <td><strong>Benchmark</strong> </td> <td><strong>gpt-oss-120b </strong> </td> <td><strong>gpt-oss120b-w-mxfp4-a-fp8(this model)</strong> </td> <td><strong>Recovery</strong> </td> </tr> <tr> <td>AIME25 </td> <td>65.25 </td> <td>67.12 </td> <td>102.87% </td> </tr> <tr> <td>GPQA </td> <td>51.67 </td> <td>53.42 </td> <td>103.39% </td> </tr> </table>
Reproduction
The results of AIME25 and GPQA Diamond were obtained using gpt_oss.evals with low effort setting, and vLLM docker rocm/vllm-private:rocm7.0_ubuntu_22.04_vllm_0.10.1_instinct_gptoss_wmxfp4_afp8_20251030.
Launching server
vllm serve amd/gpt-oss120b-w-mxfp4-a-fp8 \
--tensor_parallel_size 2 \
--gpu-memory-utilization 0.90 \
--no-enable-prefix-caching \
--max-num-batched-tokens 1024Evaluating model in a new terminal
python -m gpt_oss.evals --model /shareddata/amd/gpt-oss120b-w-mxfp4-a-fp8 --eval aime25,gpqa --reasoning-effort low --n-threads 128License
Modifications Copyright(c) 2025 Advanced Micro Devices, Inc. All rights reserved.
