LLM Inference Benchmark Explorer
Step-5-Preview on DGX B300 — FP8, vLLM, TP4, speculative decoding k=3 inference benchmark
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| Model | Step-5-Preview |
|---|---|
| Parameters | 604B |
| Intelligence Index | 43.7 |
| Agentic Index | — |
| Device | DGX B300 |
| Quantization | FP8 |
| Max C | 128 |
| Chat Capacity | 512 |
| Agentic Capacity | 141 |
| TP | 4 |
| DP | — |
| PP | — |
| Engine | vLLM |
| Speculative Decoding | Yes |
| C | TTFT (ms) | TPS (tok/s) | Status |
|---|---|---|---|
| 1 | 51 | 145.08 | PASS |
| 2 | 72 | 134.24 | PASS |
| 4 | 79 | 108.05 | PASS |
| 8 | 98 | 89.37 | PASS |
| 16 | 130 | 74.17 | PASS |
| 32 | 155 | 62.30 | PASS |
| 64 | 178 | 51.78 | PASS |
| 128 | 264 | 37.87 | PASS |
| 256 | 731 | 15.11 | FAIL |
In OpenZeka's measurement, Step-5-Preview (604B parameters), served in FP8 format with vLLM and speculative decoding on DGX B300 (TP=4), reached a generation speed of 145.1 tok/s per request and a time to first token (TTFT) of 51 ms with a single request.
Considering the speed targets and the available KV cache capacity, the estimated capacity is 512 users for chat use and 141 for agentic use. The realistic capacity will likely fall between these two values. In scenarios dominated by coding, tool use, long workflows and multi-agent use, capacity approaches the agentic estimate; where shorter interactions, standard conversations and lighter tasks dominate, it approaches the chat estimate.
Notes: Served as stepfun-ai/Step-5-Preview-expert (same checkpoint). Expert parallelism EP=4. Speculative MTP k=3.
Intelligence Index and Agentic Index values are published by Artificial Analysis and are reproduced here with attribution.
In OpenZeka's measurement, Step-5-Preview (604B parameters), served in FP8 format with vLLM and speculative decoding on DGX B300 (TP=4), reached a generation speed of 145.1 tok/s per request and a time to first token (TTFT) of 51 ms with a single request.
Considering the speed targets and the available KV cache capacity, the estimated capacity is 512 users for chat use and 141 for agentic use. The realistic capacity will likely fall between these two values. In scenarios dominated by coding, tool use, long workflows and multi-agent use, capacity approaches the agentic estimate; where shorter interactions, standard conversations and lighter tasks dominate, it approaches the chat estimate.