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‹ RTX PRO 4500 Blackwell

Qwen3.8-Flash-Next

EXL3 2.05 bpw · tabbyapi · 256K context · RTX PRO 4500 Blackwell · 32 GB

Qwen3.8's large mixture-of-experts model: far more knowledge than the 27B, with few active parameters, so it stays fast.

23 tok/sdecode
– tok/sprefill
256Kcontext window
Earlier checkSep 19, 2026
Run it

Follow the steps below to download and run this recipe. Omarchy Local AI lists the recipes it can launch on your hardware. The server then answers on http://localhost:8000/v1.

  1. 1 Download the weights
    hf download turboderp/Qwen3.8-Flash-Next-exl3 \
      --revision 65c895314393431c09050b2e04e250836b3a6eb4 \
      --local-dir ~/models/Qwen3.8-Flash-Next-exl3-65c89531
  2. 2 Write the server config
    cat > qwen3.8-flash-next.tabbyapi.256k.yml <<'EOF'
    network:
      host: 0.0.0.0
      port: 5000
      disable_auth: true
      disable_fetch_requests: true
      send_tracebacks: false
      api_servers: ["OAI"]
      sse_ping_interval: 15
    
    logging:
      log_prompt: false
      log_generation_params: false
      log_requests: false
      log_chat_completion_requests: false
    
    model:
      model_dir: /workspace/models
      inline_model_loading: false
      use_dummy_models: false
      model_name: Qwen3.8-Flash-Next-EXL3-205bpw-H4
      backend: exllamav3
      max_seq_len: 262144
      cache_size: 262656
      cache_mode: Q4
      tensor_parallel: false
      gpu_split_auto: true
      autosplit_reserve: [512]
      chunk_size: 2048
      output_chunking: true
      max_batch_size: 2
      vision: true
      reasoning: true
      start_in_reasoning: always
      reasoning_start_token: " thinking"
      reasoning_end_token: "</think>"
      template_vars_default:
        enable_thinking: true
      tool_format: qwen3_coder
      # The 26.24 GB n-gram table is indexed by short n-grams and never needs to
      # be on the card, so it lives in host RAM. 51B of routed-expert weights are
      # then split off the card so what stays resident fits a 24 GB board, and the
      # split is chosen from the measured free memory rather than guessed.
      ngram_ram: true
      cpu_moe_split_experts: 128
      draft_model:
        draft_mode: mtp
    EOF
  3. 3 Start the server
    docker run --rm \
      --gpus all \
      -p 8000:5000 \
      --shm-size 8g \
      -e NVIDIA_VISIBLE_DEVICES=all \
      -v ~/models/Qwen3.8-Flash-Next-exl3-65c89531:/workspace/models:ro \
      -v $PWD/qwen3.8-flash-next.tabbyapi.256k.yml:/app/config.yml:ro \
      --entrypoint /opt/venv/bin/python3 \
      ghcr.io/theroyallab/tabbyapi:cu13@sha256:1c13dd17416660856e9962aeee8498827f0acd604eb36795128a03ddfe03c6ef \
      main.py \
      --config /app/config.yml
What it passed
✓ loadLoads and serves within an hour
✓ chatAnswers a plain question and stops on its own
✓ reasoningThinks separately and gets 17 × 23 right
✓ toolsCalls a tool with the right arguments and uses the result
– contextRecalls a code buried in a prompt that fills 85% of the window
– speedDecodes at 15 tok/s or more

Passed the older check (loads and chats); a full six-check run is pending.

Details
Weights
turboderp/Qwen3.8-Flash-Next-exl3 @ 65c8953143 ›
Image
ghcr.io/theroyallab/tabbyapi:cu13@sha256:1c13dd17416660856e9962aeee8498827f0acd604eb36795128a03ddfe03c6ef
Launch
tabbyapi-qwen3.8-flash-next-2.05bpw-h4-ng4-256k ›
Recipe file
registry/recipes/nvidia/rtx-pro-4500-blackwell-32gb/qwen3.8-flash-next.tabbyapi.256k.json ›
Model released
Aug 24, 2026
Tested
earlier acceptance