Qwen3.8-27B — FP8 block + AWQ
FP8 block-scaled [128, 128] quantization of Qwen/Qwen3.8-27B with dynamic
activations — the same format and the same 882 excluded modules as Qwen's own
FP8 release — with one addition they do not use: an AWQ smoothing pre-pass
on the BF16 weights.
That single change cuts real damage by 45%: 1.45% → 0.79% confident disagreement, z = +9.80.
Drop-in for vLLM. ~30 GB, 8,656 tok/s (TP=2, B300).
Measured quality
Every row measured identically: 231 documents, 142,727 scored token positions, against the BF16 base.
| build | size | top-1 ↑ | near-tie ↓ | moderate ↓ | confident ↓ | certain ↓ | divmed ↑ | tok/s |
|---|---|---|---|---|---|---|---|---|
| ➤ this model — FP8 block + AWQ | 30 GB | 96.22% | 22.83% | 3.76% | 0.79% | 0.08% | 51 | 8656 |
| TelperionAI INT4-AWQ-GPTQ | 25.1 GB | 96.30% | 22.29% | 3.52% | 0.93% | 0.09% | 48 | 4617 |
| TelperionAI EXL3 6.5 bpw + AWQ | 23.0 GB | 97.10% | 17.03% | 2.41% | 1.23% | 0.15% | 59 | — |
| TelperionAI EXL3 5.5 bpw + AWQ | 20.0 GB | 96.12% | 22.81% | 3.52% | 1.34% | 0.16% | 55 | — |
| Qwen FP8 (same format, no AWQ) | 30 GB | 96.15% | 22.70% | 3.48% | 1.45% | 0.08% | 47 | 8711 |
| TelperionAI NVFP4 | 24.7 GB | 93.62% | 32.25% | 8.59% | 1.85% | 0.16% | 29 | 10521 |
| RadixArk NVFP4 | 24.7 GB | 90.23% | 43.80% | 14.49% | 3.29% | 0.70% | 11 | 11436 |
| unsloth NVFP4 | 24.7 GB | 91.75% | 40.12% | 10.32% | 3.91% | 0.25% | 19 | 11069 |
| Inferact NVFP4 | 20.1 GB | 84.11% | 52.01% | 25.70% | 10.39% | 2.27% | 7 | 11457 |
EXL3 rows have no comparable tok/s — they run on exllamav3, not vLLM.
How to read this
Columns are disagreement rates against the BF16 base, split by how confident the base model was at that position (its top1−top2 logprob margin):
| bucket | margin | meaning |
|---|---|---|
near-tie |
< 0.5 | numerical noise — harmless |
moderate |
0.5–2 | mild |
confident |
2–5 | real damage |
certain |
> 5 | real damage |
Only confident and certain matter. divmed is the median token index at
which free greedy generation first diverges from the base.
Significance
Paired McNemar over matched token positions, n = 33,812:
| vs | their confident | z | verdict |
|---|---|---|---|
| TelperionAI NVFP4 | 1.85% | +14.80 | this model better |
| Qwen FP8 (same format) | 1.45% | +9.80 | this model better |
| TelperionAI EXL3 5.5bpw+AWQ | 1.34% | +9.14 | this model better |
| TelperionAI EXL3 6.5bpw+AWQ | 1.23% | +7.43 | this model better |
| TelperionAI INT4-AWQ-GPTQ | 0.93% | +2.46 | this model better |
It also ties the best certain figure in the field (0.08%).
Recipe
- AWQ smoothing on the BF16 weights — a pure, function-preserving transform
(fold
1/sinto the preceding norm,sinto the next linear's input dim), calibrated on 256 sequences. Verified function-preserving: the ratio to the original weights is a separable per-row × per-column scale. - FP8 block
[128,128]weights with dynamic per-group activations, excluding the same 882 modules Qwen excludes. This stage needs no calibration — weight scales come from the weight tensor alone and activations are scaled at runtime.
Note that the 882 exclusions are not conservatism: FP8 block requires every
quantized dimension to be divisible by 128, and the router / shared_expert_gate
layers are not.
Why AWQ helps at 8 bits
AWQ corrects activation outliers, which are a property of the model rather
than of the quantizer — so it transfers across formats. Measured on this model:
NVFP4 3.97% → 2.69%, a 4-bit trellis 3.08% → 2.40%, and block FP8 1.45% → 0.79%.
A [128,128] block still spans a wide dynamic range, so outlier channels cost
real precision even at 8 bits.
GPTQ and AutoRound do not transfer this way: they are quantizers whose error compensation is tied to specific rounding decisions on a specific grid.
- Downloads last month
- 10
Model tree for TelperionAI/Qwen3.8-27B-FP8-block-AWQ
Base model
Qwen/Qwen3.8-27B