// ANTONYMOX · PARK RECORD · SMARTEST BUILD
Qwen3.6-27B wide — INT4 · MTP
The clean Qwen3.6-27B base, quantized our way — big linear-attention projections kept in BF16. Highest hard-coding score in our fleet (78), MTP head preserved, sees images, up to 256k context (native).
hard 78 · record
MTP preserved
vision
256k ctx
26 GB
Apache-2.0
📊 All benchmarks & throughput measured on a single RTX 4090 (48 GB) · vLLM 0.19 · MTP n=3 · seed 42
The clean Qwen/Qwen3.6-27B base (no distill, no abliteration — creator alignment intact),
quantized by us with AutoRound INT4 using a wide recipe: the large linear-attention (SSM/GDN)
projections are kept in BF16 instead of INT4. That single choice lifts hard-coding from 70 → 78
(+8 pp) over the standard narrow quant — the highest hard score in our fleet, at a third the size
of the 80B it beats. MTP head preserved → speculative decoding works in vLLM out of the box.
Highlights
🏆 Fleet record — hard 78
our smartest build; beats the 80B Coder-Next (62) at ⅓ the size
🧠 Clean base, no distill
raw Qwen3.6-27B intelligence, not a fine-tune
🔬 The "wide" trick: +8 pp
big SSM projections kept BF16 → long-range logic survives
🧬 MTP preserved
15-tensor head kept → speculative decoding just works
🖼️ Multimodal
images & video — vision tower full BF16
📏 256k context (native)
supports 256k; full 256k fits on 48 GB at mem 0.80
⚡ 83 tok/s — brisk for dense
MTP n=3; not a slow model despite being dense
🧾 Proof in-repo
the per-task benchmark JSON ships with it
Benchmarks — the wide trick pays off
Same clean base Qwen/Qwen3.6-27B, one harness — only the quant recipe changes. Keeping the big
SSM projections in BF16 lifts hard +8 pp over the standard narrow quant:
+8 pp hard for +7.5 GB over narrow — and it beats
Qwen3-Coder-Next 80B (hard 62 on our harness), three times its size.
[!NOTE]
Numbers are
% of tasks passed (40 hard coding + 30 tool tasks; raw pass/total in
benchmark-results/). Conditions: temp 1.0 / top_p 0.95 / top_k 20 / min_p 0 ·
seed 42 · non-thinking · vLLM 0.19 · RTX 4090 (48 GB) · MTP n=3. The abliterated & wide rows share the
exact 40 hard tasks the narrow quant scored 70 on → clean apples-to-apples. The
Lorbus row is our own
measurement of their public quant, not their claim. The
80B Coder-Next row is likewise our own
measurement of the UD-IQ4_XS GGUF (via LM Studio) on the same task set — a bigger, different model shown
for scale. Reproduce it, don't trust it.
🔬 The "wide" trick — why it scores higher
Qwen3.6 is a hybrid model: most layers are linear-attention (GDN/Mamba), where long-range logic
flows through the large projections in_proj_qkv, in_proj_z, out_proj. Standard "narrow" INT4
quants compress these to 4-bit too — and that quietly costs reasoning. We keep them in BF16:
| Kept in BF16 (not quantized) | Tensors | Why |
|---|
| 🔬 Big SSM projections (the wide trick) | in_proj_qkv, in_proj_z, out_proj | carry long-range logic — INT4 here costs ~8 pp hard |
| 🌊 Small SSM control | A_log, conv1d, dt_bias, in_proj_a/b, norm | SSM recurrence stability |
| 🧬 MTP head | 15× mtp.* | makes speculative decoding work |
| 👁️ Vision tower | 333× visual.* | full image/video, untouched |
Everything else (full-attention q/k/v/o, MLP gate/up/down) is INT4. The recipe was validated on
Qwen3.5 first (+6 pp) and confirmed here on 3.6 (+8 pp).
⚡ Speed — MTP speculative decoding
Honest 768-token × 3-run measurement on a single RTX 4090 (48 GB), vLLM 0.19:
MTP n | short tok/s | 28k-ctx tok/s | acceptance @28k |
|---|
| 1 | 55 | 33 | 79% |
| 2 | 71 | 39 | 64% |
| 3 ⭐ | 83 | 40 | 52% |
| 4 | 92 | 42 | 44% |
| 5 | 96 | 40 | 37% |
Use num_speculative_tokens: 3 — long-context throughput is already on its plateau (~40 tok/s)
while acceptance stays highest (52%), so the draft head misfires least. Spec-decode is lossless —
n changes speed only, never output.
🖼️ Multimodal — sees images & video
The full vision-language model. The entire vision tower (333 tensors) is kept in full BF16 —
quantization never touched it — so image/video understanding is identical to the pristine base.
Serve with --limit-mm-per-prompt '{"image":4,"video":1}'. Published benchmarks cover text/coding/tool-use;
vision quality is inherited from the base, not separately re-scored.
🚀 Quickstart — this is a big-card model
Weights are 26 GB, so this is a big-card model. A 48 GB card is its home; a 32 GB card
runs it but with only a small context window; 24 GB can't load it at all.
| GPU | VRAM | Script | max-model-len | gpu-mem-util | Status |
|---|
| RTX 4090 48G / A6000 / L40S / RTX 6000 | 48 GB | run_48gb.sh | 150 000 | 0.72 | ✅ tested (benchmark rig) |
| RTX 5090 | 32 GB | run_32gb.sh | 16 384 | 0.95 | ✅ verified (tight; dedicated card) |
| RTX 3090 / 4090 | 24 GB | — | — | — | ❌ 26 GB weights don't fit |
[!NOTE]
32 GB is tight. The 26 GB weights leave only ~1.7 GB for KV even at mem-util 0.95, so the safe
window is ~16k tokens (measured by emulating a 32 GB budget on a 48 GB card: concurrency ~1.5x at
16k; 24k dropped to 1.03x = the hang zone). mem 0.95 assumes a
dedicated/headless card — lower it
if a display is attached.
Want long context on ≤ 32 GB? Use the 19 GB
abliterated sister
(fits 24 GB with 40k ctx, or 32 GB with much more).
1vllm serve antonyMox/Qwen3.6-27B-AutoRound-INT4-wide-MTP \
2 --quantization auto-round \
3 --max-model-len 150000 \
4 --gpu-memory-utilization 0.72 \
5 --max-num-seqs 1 \
6 --kv-cache-dtype fp8_e4m3 \
7 --enable-prefix-caching \
8 --enable-auto-tool-choice --tool-call-parser qwen3_coder \
9 --reasoning-parser qwen3 \
10 --speculative-config '{"method":"mtp","num_speculative_tokens":3}' \
11 --trust-remote-code
Long context is cheap: Qwen3.6 is a hybrid (Mamba/GDN + attention), KV costs ~37 MB/1k tokens at fp8.
The model's native maximum is 256k (262,144) tokens — how much fits on 48 GB depends on mem-util:
Context vs mem-util (48 GB card, measured)
gpu-mem-util | context that fits | notes |
|---|
| 0.72 ⭐ (default preset) | ~150k (conc 1.15x) | balanced; leaves VRAM free |
| 0.80 | 256k (conc 1.11x) | full native context |
Raise --gpu-memory-utilization toward 0.80 for the full 256k; the 0.72 default keeps more VRAM free
(this variant's 26 GB weights leave less room than the 19 GB abliterated sister).
[!WARNING]
Never set --max-model-len at exact KV capacity. On vLLM 0.19 hybrid models, requests in the
last ~3 % of the window pass validation then hang forever (no error, GPU idle) — the scheduler
can't allocate the final KV block. Keep the window a couple of blocks below capacity: after launch,
the log line Maximum concurrency for N tokens: Yx must be ≥ ~1.10x (ours is 1.15x at 150k),
never 1.00x. Also, the GPU KV cache size: X tokens log line understates real capacity ~3× on
hybrids — trust only the Maximum concurrency line.
🧬 The family
Clean quants of the same base — pick by hardware:
| Model | Size | hard | tools | Best for |
|---|
| ➡️ wide (this) | 26 GB | 78 🏆 | 83 | 48 GB+ cards — maximum reasoning |
| abliterated | 19 GB | 70 | 87 | 24 GB cards · uncensored |
| 35B-A3B (coming soon) | 22 GB | 48 | 83 | fast MoE (~188 tok/s) |
The 27B sisters: AutoRound INT4, MTP preserved, multimodal. All benchmarked against the community
reference
Lorbus narrow INT4 (hard 70) — see the table above.
🍳 Recipe (reproducible)
- Base — pristine
Qwen/Qwen3.6-27B BF16.
- Quant — AutoRound W4A16, group 128, 200 iters, v2 calibration.
- Wide fp_layers (kept BF16) —
mtp.*, visual.*, small SSM (in_proj_a/b, A_log, conv1d,
dt_bias, linear_attn.norm) + the wide trick: in_proj_qkv, in_proj_z, out_proj.
- MTP — 15
mtp.* tensors preserved (BF16), n=3 recommended.
- Sampler — ships temp 1.0 / top_p 0.95 / top_k 20 (
generation_config.json).
🔢 Why HuggingFace shows "~11.5B params"
Not a small model — it's how the widget reads a partially-packed INT4 quant. The INT4 weight
tensors are packed 8× int4 into each int32 (HF counts fewer slots), while the large wide projections,
vision, and MTP stay full BF16 (counted fully). The true model is Qwen3.6-27B, 26 GB on disk.
Verified breakdown: language_model 9.35 B · other 1.27 B · vision 0.46 B (333 t, BF16) ·
mtp 0.42 B (15 t, BF16). (The wide sister shows more BF16 than a narrow quant precisely because it
keeps those big projections full-precision — that's the whole point.)
📜 License & attribution
Apache-2.0, same as the base. Quantized from
Qwen/Qwen3.6-27B with a wide AutoRound INT4 recipe.
This is the clean base (creator safety alignment intact). Community build; benchmark numbers are from
our own harness — JSON included, methodology open. Provided "as is", without warranty.