Qwen3.8-27B-TWIN-TURBO-Fable-Cold-Fusion-709-L-Uncensored-NVFP4-W4A16-T336

NVFP4 checkpoint of DavidAU/Qwen3.8-27B-TWIN-TURBO-Fable-Cold-Fusion-709-L-Uncensored, quantized for vLLM serving. NVFP4 here means W4A16 with FP8 scales, group size 16, weight only, 336 tensors. No calibration data was used.

HF repo: esatapedico/Qwen3.8-27B-TWIN-TURBO-Fable-Cold-Fusion-709-L-Uncensored-NVFP4-W4A16-T336

At a glance

Quantized set covers the MLP on all 64 layers (192 tensors) plus the DeltaNet in_proj_qkv/z/out_proj tensors on the 48 linear-attention layers (144 tensors). Full-attention projections and token embeddings stay at full precision, where precision buys the most quality; the lm_head stays at full precision because vLLM runs the output head unquantized regardless. Vision tower, MTP head, and DeltaNet conv1d plus in_proj_a/b dynamics stay at full precision following the JC1DA exception pattern.

Serving

Built for vLLM and engines consuming vLLM-compatible compressed-tensors checkpoints. Verified serving: tensor parallel 2, 2048 context, coherent generation. Measured perplexity on a diverse English payload is on par with the 256-tensor parent checkpoint (3.19 vs 3.20), so the DeltaNet quantization costs nothing measurable. Serve with --quantization compressed-tensors semantics (auto-detected from the config); FP8 KV remains a runtime flag, not checkpoint bytes. Keep vision intact and MTP for speculative decoding; no GGUF inside this repo.

Checkpoint

• Single model.safetensors about 21 GB
• config.json quantization_config.format=nvfp4-pack-quantized, quant_method=compressed-tensors, Qwen3_5ForCausalLM, 64 layers, hybrid GatedDeltaNet, 262144 context, MTP head
• tokenizer.json intact, chat template intact

Provenance

Derivative of DavidAU/Qwen3.8-27B-TWIN-TURBO-Fable-Cold-Fusion-709-L-Uncensored (Apache 2.0) which itself derives from Qwen/Qwen3.8-27B. The TWIN-TURBO tune targets reduced thinking tokens with matched output quality. Sibling checkpoints: the conservative 256-tensor GGUF parent at esatapedico/Qwen3.8-27B-TWIN-TURBO-Fable-Cold-Fusion-709-L-Uncensored-NVFP4 and the 400-tensor serving build at esatapedico/Qwen3.8-27B-TWIN-TURBO-Fable-Cold-Fusion-709-L-Uncensored-NVFP4-W4A16-T400.

Follow along & support

I post updates on new conversions, benchmarks, and what I'm working on over on my site. Follow along there to keep up with new releases and the work in progress. If you'd like to support more of it, you will find the options there. I do this on consumer hardware and like seeing how far it goes. More is on the way.

🌐 esatapedico.com. Updates, work-in-progress, and ways to support.

License

apache-2.0

Card written with AI assistance.