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Research

Quantization

Smaller models that preserve the quality of their answers.

BBQ-FP4 is our own 4-bit quantization. It cuts model-weight memory by 3.2x to 3.8x while matching or exceeding full precision on average benchmark recovery.

3.2–3.8x

smaller model-weight footprint than bf16

101.4%

average recovery vs bf16 on Qwen3-30B-A3B (101.3% on Qwen3-Next-80B-A3B)

2.67x

decode throughput at best: 6,151 tok/s vs 2,304 in bf16 on Qwen3-30B-A3B

The weights, to scale.

Model-weight memory in bf16 and in BBQ-FP4. One block is 8 GB.

Qwen3-30B-A3B

bf1657 GB
BBQ-FP416 GB

Qwen3-Next-80B-A3B

bf16152 GB
BBQ-FP440 GB

Against another 4-bit build of the same size.

Both 4-bit builds use about the same memory. Higher recovery and lower KLD mean a closer match to bf16.

Metric

bf16

BBQ-FP4

External w4a16

BBQ edge

Qwen3-30B-A3B

Avg. recovery

100.0%

101.4%

99.7%

+1.7 pts

Worst-case recovery

100.0%

98.5%*

98.1%

+0.4 pts

WikiText KLD

0

0.0345

0.0733

2.1x lower

Weight memory

57 GB

16 GB

~16 GB

same footprint

Qwen3-Next-80B-A3B

Avg. recovery

100.0%

101.3%

97.8%

+3.5 pts

Worst-case recovery

100.0%

94.8%

93.1%

+1.7 pts

WikiText KLD

0

0.0285

0.0329

13% lower

Weight memory

152 GB

40 GB

~41 GB

~same footprint

What this means for cloud providers

Increase deployable model capacity within existing GPU memory envelopes. The same compression class becomes a quality differentiator, not just a cost lever.

Where BBQ is strongest

Quality-sensitive MoE serving where benchmark regressions, distribution drift, and GPU memory ceilings matter as much as raw model compression.

Methodology: post-training FP4 quantization of Qwen3 MoE models. Recovery and memory savings are relative to bf16. External comparison values marked ~ are extrapolated, not directly benchmarked. Standard benchmarks are proxies and may not represent all production workloads.

* Qwen3-30B-A3B worst-case recovery is for BBQ-FP4-S; BBQ-FP4-L reached 100.7%.

The code is not public yet.

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