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Llama-3.1-405B-FP8

Open Source meta-llama Released 2024-07-23
8.0 / 100 405.0B params 128K context Open Source

About this model

Llama 3.1 405B FP8 is Meta's official FP8-quantized variant of the Llama 3.1 405B Instruct model, released in July 2024 as part of the Llama 3.1 family. It applies 8-bit floating-point quantization to major linear layers (covering roughly 75% of inference FLOPs), cutting weight memory roughly in half versus BF16 while preserving near-identical accuracy on standard benchmarks. Independent evaluations report ~99.99% score recovery versus the full-precision instruct model, making it practical to run the world's largest open-weights LLM on a single 8-GPU node.

The underlying Llama 3.1 405B model is a 405-billion-parameter autoregressive transformer with grouped-query attention (GQA), pretrained on over 15 trillion tokens and instruction-tuned with SFT and RLHF for multilingual dialogue. It supports a 128K-token context window and eight languages (English, German, French, Italian, Portuguese, Hindi, Spanish, and Thai), with strong performance across knowledge, reasoning, math, and coding tasks. On Meta's internal benchmarks the instruct model reaches 87.3% on MMLU, 96.8% on GSM-8K (CoT), 89.0% on HumanEval, and 73.8% on MATH (CoT).

Released under the Llama 3.1 Community License, the FP8 checkpoint is intended for commercial and research deployment where single-node inference efficiency matters. It is compatible with mainstream serving stacks including vLLM, TensorRT-LLM, and Hugging Face Transformers, and is recommended for assistant-style chat, tool use, long-context applications, synthetic data generation, and distillation workflows.

Benchmark Scores

ARC
96.9
BBH
89.2
DROP
84.8
GPQA
50.7
MATH
73.8
MBPP
88.6
MMLU
87.3
GSM8K
96.8
IFEval
88.6
AGIEval
71.6
MMLU-Pro
73.3
SimpleQA
17.1
HellaSwag
88.5
HumanEval
89.0
TruthfulQA
65.3
LiveCodeBench
30.2

Technical Specs

  • Parameters: 405.0B
  • Architecture: Transformer
  • Context Window: 128,000 tokens
  • Input Modalities: text

Hardware Requirements

  • VRAM: 405.0 GB
  • Compute: 8x NVIDIA H100 80GB GPUs with tensor parallelism (FP8 weights; ~405 GB model memory)