---
id: pr-vllm-19563
repo: vllm-project/vllm
pr: 19563
title: '[Quantization] Remove FP4 emulation; Fall-back to marlin for device < 100'
author: dsikka
date: '2025-06-16'
url: https://github.com/vllm-project/vllm/pull/19563
source_category: upstream-code
architectures:
- sm100
tags: []
techniques: []
hardware_features: []
kernel_types: []
languages: []
captured_at: '2026-05-16'
status: merged
merge_sha: 6bc7b573153afebe51de036f9b28d37ff6cbb733
inclusion_reason: defer
changed_paths:
- tests/quantization/test_compressed_tensors.py
- vllm/model_executor/layers/quantization/compressed_tensors/compressed_tensors.py
- vllm/model_executor/layers/quantization/compressed_tensors/schemes/compressed_tensors_w4a16_nvfp4.py
- vllm/model_executor/layers/quantization/compressed_tensors/schemes/compressed_tensors_w4a4_nvfp4.py
- vllm/model_executor/layers/quantization/utils/nvfp4_emulation_utils.py
artifact_dir: evidence/pull-bundles/vllm/gh-19563
head_ref_oid: 9b501e577678fb6124a87c3daaf875ce6de131ab
---
# [Quantization] Remove FP4 emulation; Fall-back to marlin for device < 100

- Repository: `vllm-project/vllm`
- PR: [19563](https://github.com/vllm-project/vllm/pull/19563)
- Decision: `defer`
- Reason: defer

## Changed Paths

- `tests/quantization/test_compressed_tensors.py`
- `vllm/model_executor/layers/quantization/compressed_tensors/compressed_tensors.py`
- `vllm/model_executor/layers/quantization/compressed_tensors/schemes/compressed_tensors_w4a16_nvfp4.py`
- `vllm/model_executor/layers/quantization/compressed_tensors/schemes/compressed_tensors_w4a4_nvfp4.py`
- `vllm/model_executor/layers/quantization/utils/nvfp4_emulation_utils.py`

## Evidence Bundle

`evidence/pull-bundles/vllm/gh-19563`
