What problem does it solve?
GPTQ reduces the memory footprint of large language models while keeping quality close to FP16, so you can run much bigger models on limited consumer or single-server GPU resources.
Core Features & Use Cases
- Post-training 4-bit quantization: Compresses pretrained LLM weights to 4-bit using group-wise quantization with minimal accuracy loss.
- Calibration-driven accuracy control: Uses representative calibration data to minimize quantization error and preserve perplexity.
- Optimized inference backends: Supports multiple kernel backends (e.g., ExLlama, Marlin, Triton) for faster generation.
Use cases: deploy 70B–405B-class models on consumer GPUs, reduce VRAM needs for serving, and enable faster inference when FP16 is too large or too slow.
Quick Start
Use the gptq skill to quantize Llama-2-7B-Chat from HuggingFace by running the quantization with 4-bit group size 128 on a small calibration sample and saving the resulting quantized model directory.