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copy-paste woes - NVFP4A16 can be run without hardware NVFP4
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---
license: llama3.3
base_model:
- invisietch/L3.3-Ignition-v0.1-70B
pipeline_tag: text-generation
tags:
- text adventure
- roleplay
- rpg
- creative writing
- nvfp4
- vllm
- conversational
- nvfp4a16
---
# L3.3-Ignition-v0.1-70B (NVFP4A16 quant)
This repo contains L3.3-Ignition-v0.1-70B quantized with NVFP4A16, a 4-bit compression suitable for max performance on all hardware with 8-bit-like accuracy.
> ℹ️ Unlike NVFP4 format (4-bit weights + 4-bit activation), NVFP4A16 is not limited to Blackwell GPUs and will be supported efficiently in vLLM with RTX 3000s and RTX 4000s GPUs.
- Original Model:
- [invisietch/L3.3-Ignition-v0.1-70B](https://huggingface.co/invisietch/L3.3-Ignition-v0.1-70B)
- Hopper and Blackwell optimized model:
- [mratsim/L3.3-Ignition-v0.1-70B-NVFP4](https://huggingface.co/mratsim/L3.3-Ignition-v0.1-70B-NVFP4)
This model requires ~39.8GiB of VRAM.
Make sure to set an appropriate context size `--max-model-len` in VLLM and/or quantize the KV cache and/or use multiple GPUs with for example tensor-parallelism.
NVFP4 writeups:
- https://developer.nvidia.com/blog/introducing-nvfp4-for-efficient-and-accurate-low-precision-inference/
- https://arxiv.org/pdf/2509.25149
## 📥 Usage & Running Instructions
The model was tested with vLLM + 1x or 2x RTX Pro 6000, here is a script suitable for such configuration with 131072 context length.
### Recommendations
It is however recommended to use only 65K context to avoid significant degradation (https://fiction.live/stories/Fiction-liveBench-Sept-29-2025/oQdzQvKHw8JyXbN87)
This model is recommended with "min-p" sampling, this sampling is available through
both the oldest Text completions API and the Chat completions API (and there is a new Response API),
however most LLM frontends only support modifying min-p when using Text completions.
You can however use `--override-generation-config "${SAMPLER_JSONCONFIG}"` to override the sampler (which is a merge of generation_config.json and vLLM defaults)
### Running script
```bash
# Model configuration (Mandatory)
MODEL="mratsim/L3.3-Ignition-v0.1-70B-NVFP4A16"
MODELNAME="L3.3-Ignition-v0.1-70B"
GPU_UTIL=0.45
NUM_GPUS=2
# Sampling configuration (Optional, if departing from `generation_config.json`)
SAMPLER_OVERRIDE='{"temperature": 1, "min_p": 0.03, "repetition_penalty": 1.03}'
# Prevent vLLM from using 100% CPU when idle (Very Recommended)
export VLLM_SLEEP_WHEN_IDLE=1
# Use FlashInfer backend (fastest, recommended, "instant" context reprocessing)
export VLLM_ATTENTION_BACKEND=FLASHINFER
vllm serve "${MODEL}" \
--served-model-name "${MODELNAME}" \
--tensor-parallel-size "${NUM_GPUS}" \
--gpu-memory-utilization ${GPU_UTIL} \
--override-generation-config "${SAMPLER_OVERRIDE}"
```
> ℹ️ The FlashInfer backend may fail with an error similar to
> `Failed to allocate memory for batch_prefill_tmp_v with size XYZ and alignment 16 in AlignedAllocator`.
>
> A workaround is running a sed replacement command within vllm install to increase buffer space
> ```bash
> sed -i 's/FLASHINFER_WORKSPACE_BUFFER_SIZE = 256 \* 1024 \* 1024/FLASHINFER_WORKSPACE_BUFFER_SIZE = 512 \* 1024 \* 1024/g' vllm/v1/attention/backends/flashinfer.py
> ```
> This will be fixed by PR https://github.com/vllm-project/vllm/pull/25344
## 🔬 Quantization method
The llmcompressor library was used with the following recipe:
```yaml
default_stage:
default_modifiers:
QuantizationModifier:
targets: [Linear]
ignore: [lm_head]
scheme: NVFP4A16
```
NVFP4A16 doesn't require any calibration dataset.