On-prem models / StepFun

Run Step-3.7-Flash on-prem

198B sparse MoE vision-language model (196B language backbone plus 1.8B vision encoder, about 11B active) built for high-throughput agent workloads. Official FP8, NVFP4 and GGUF variants exist.

198B MoE (11B active)256K contextApache-2.0text + visionthinking modetool callingreleased 2026-05

Memory needed

PrecisionWeightsKV per request, 8KKV per request, 32KKV per request, 128K
BF16 (full precision)396 GB0.47 GB1.68 GB6.51 GB
FP8198 GB0.24 GB0.84 GB3.26 GB
INT4 (AWQ / GPTQ)111 GB0.24 GB0.84 GB3.26 GB
GGUF Q4_K_M119 GB0.24 GB0.84 GB3.26 GB

KV cache from the published config: 45 layers, 8 KV heads x 128 dims, 33 sliding-window layers (512 tokens). 16-bit cache for BF16 rows, 8-bit otherwise.

Fit for ERP and manufacturing work

Good fit for document-heavy finance and procurement agents (reports, invoices, POs) that need vision plus tool use under a permissive licence. NVFP4 build makes a 4-GPU Blackwell deployment plausible.

Strengths

  • Apache 2.0
  • Broad engine coverage including official llama.cpp fork and GGUF
  • Sliding-window layers keep KV small
  • Card highlights parsing large financial reports and multi-step search agents

Watch out for

  • About 400 GB in BF16; FP8 or NVFP4 recommended
  • Some features need StepFun's vLLM image or SGLang dev build
  • Smaller community than Qwen/GLM

GPUs that run it

One user, 8K context, 4-bit

HardwareCountMemory usedTok/s per user
AMD Instinct MI210 64GB2115 / 115 GB138
Intel Gaudi 3 128GB (HL-325L OAM)1113 / 115 GB189
NVIDIA DGX Spark (GB10) 128GB1113 / 115 GB19
AMD Ryzen AI Max+ 395 128GB system1113 / 115 GB18
NVIDIA H200 SXM 141GB1113 / 126 GB226
NVIDIA H200 NVL 141GB1113 / 126 GB226
NVIDIA A100 40GB PCIe4118 / 144 GB168
NVIDIA A100 80GB PCIe2115 / 144 GB156

20 people at once, 16K context, FP8

HardwareCountMemory usedTok/s per user
AMD Instinct MI210 64GB4213 / 230 GB102
AMD Instinct MI325X 256GB1209 / 230 GB136
Intel Gaudi 3 128GB (HL-325L OAM)2210 / 230 GB130
NVIDIA B300 (Blackwell Ultra) 270GB1209 / 243 GB169
NVIDIA H200 SXM 141GB2210 / 253 GB154
NVIDIA H200 NVL 141GB2210 / 253 GB154
AMD Instinct MI355X 288GB1209 / 259 GB169
NVIDIA A100 40GB PCIe8219 / 288 GB129

Serving and licence

vLLM (vllm/vllm-openai:stepfun37 image, --tool-call-parser step3p5, --reasoning-parser step3p5), SGLang dev image, Transformers, and llama.cpp via stepfun-ai fork with official GGUF; NVFP4 needs modelopt quantisation and FP8 KV cache.

Apache-2.0. Apache 2.0: commercial use, modification and redistribution allowed with notice.

Model card on Hugging Face

Design a Step-3.7-Flash deployment

Preloaded with Step-3.7-Flash. Add your ERP and documents, change GPUs or users, and export the diagram.

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Questions

How much VRAM does Step-3.7-Flash need?

The weights alone take about 396 GB in BF16, 198 GB in FP8 and 111 GB in 4-bit. On top of that each request holds a KV cache of about 0.24 GB at 8K tokens of context (FP8 cache), so 20 people generating at once need roughly 4.72 GB more, plus a few GB of runtime overhead.

What is the smallest GPU setup that runs Step-3.7-Flash?

For a single user at 8K context in 4-bit, 2 x AMD Instinct MI210 64GB (64 GB each) fits, at an estimated 138 tokens per second. For a team, size for concurrent requests and context; the builder above does that.

Is Step-3.7-Flash allowed for commercial use?

Step-3.7-Flash is released under Apache-2.0. Apache 2.0: commercial use, modification and redistribution allowed with notice. Check the licence text on the model card with your legal team before production use.

Which engine should serve Step-3.7-Flash on-prem?

vLLM (vllm/vllm-openai:stepfun37 image, --tool-call-parser step3p5, --reasoning-parser step3p5), SGLang dev image, Transformers, and llama.cpp via stepfun-ai fork with official GGUF; NVFP4 needs modelopt quantisation and FP8 KV cache.