halley-ai/Qwen3-Next-80B-A3B-Instruct-MLX-4bit-gs64

Qwen3-Next-80B-A3B-Instruct — MLX 4-bit (group size 64)

Summary. This is a 4-bit (Q4) MLX quantization of Qwen3-Next-80B-A3B-Instruct with group size 64. Built for Apple Silicon with Metal acceleration.

• Base model: Qwen/Qwen3-Next-80B-A3B-Instruct (apache-2.0)
• Quantization: MLX Q4, q_group_size=64 (some tensors may remain 16-bit for stability)
• Files: MLX weight shards + config.json; tokenizer files included for drop-in use
• Intended use: lightweight local inference on M-series Macs
• Not intended for: safety-critical decisions; outputs may be inaccurate or biased

Requirements

Runs on Apple Silicon (M1 or newer) with macOS ≥ 13.5 via MLX (Metal).

• Not supported: Intel macOS / Linux / Windows (consider a GGUF build + llama.cpp instead).
• Memory guidance: large unified memory recommended (e.g., 64 GB+; 96 GB provides comfortable headroom). The effective GPU working set is capped by Metal’s budget; keep 5–10% headroom.

How to use (MLX)

pip install mlx-lm

from mlx_lm import load, generate

model, tokenizer = load("halley-ai/Qwen3-Next-80B-A3B-Instruct-MLX-4bit-gs64")
print(generate(
    model, tokenizer,
    prompt="Explain the Chudnovsky algorithm to compute π.",
    max_tokens=256, max_kv_size=512
))

python -m mlx_lm generate --model halley-ai/Qwen3-Next-80B-A3B-Instruct-MLX-4bit-gs64 \
  --prompt "Explain the Chudnovsky algorithm to compute pi." \
  --max-kv-size 512 --max-tokens 256

Evaluation

Perplexity (PPL) streaming evaluation on WikiText-2 (raw, test); fast preset with window=stride=4096, ~100k tokens, EOS inserted between docs.

Variant	PPL (ctx=4096, fast)
MLX bf16 (reference)	5.14
MLX 6-bit (gs=64)	5.14 (≈0.0% vs bf16)
MLX 5-bit (gs=32)	5.20 (+1.2% vs bf16, +1.2% vs 6b/gs64)
MLX 4-bit (gs=64)	5.43 (+5.6% vs bf16, +5.6% vs 6b/gs64)

Interpretation

• 4-bit gs64 is the smallest footprint and shows a modest PPL increase versus 5/6‑bit.
• 5-bit gs32 is a strong “quality‑light” option if you can spare ~15 GB more.
• 6-bit gs64 matches bf16 on this corpus and is the quality pick.

Reproduce locally:

python python/scripts/test_perplexity-mlx.py \
  --model_path "/path/to/Qwen3-Next-80B-A3B-Instruct-4bit-gs64" \
  --fast --progress

Conversion details (provenance)

python -m mlx_lm convert \
  --hf-path Qwen3-Next-80B-A3B-Instruct \
  --mlx-path /path/to/Qwen3-Next-80B-A3B-Instruct-4bit-gs64 \
  -q --q-bits 4 --q-group-size 64

• Some tensors (for example, embeddings/norms/router) may remain 16-bit for numerical stability.

Sibling & reference models

• halley-ai/Qwen3-Next-80B-A3B-Instruct-MLX-6bit-gs64
• halley-ai/Qwen3-Next-80B-A3B-Instruct-MLX-5bit-gs32

Verify quantization

jq '.quantization | {bits, group_size}' /path/to/export/config.json

Limitations and biases

Compared to 5‑bit/6‑bit, Q4 may show small but noticeable quality drops on some tasks (for example, perplexity, instruction following). Choose this build for footprint/throughput over maximum accuracy.

License and credits

• License: apache-2.0 (inherits from the base model)
• Base model: Qwen/Qwen3-Next-80B-A3B-Instruct
• Quantization: Halley AI Lab (MLX Q4, gs=64)
• Please cite both the base model and this repository when you use the weights.