Qwen 3.5 397B-A17B · B200 · Precision Comparison

B200: FP4 vs BF16 Precision Comparison

How FP4 and BF16 precision affect Qwen 3.5 397B-A17B inference on B200 (NVIDIA Blackwell). Throughput, latency, and cost across LLM workloads. Use the chart controls below to switch sequences and metrics — same interactions as the main inference chart.

FP4 posts 4731 tok/s/chip for $0.10 per million tokens at 112 tok/s/user on Qwen 3.5 397B-A17B (B200); BF16 posts 1216 tok/s/chip for $0.40. FP4 is 289% cheaper per token; FP4 delivers 289% more tok/s/chip. Quantization-level accuracy differences are tracked on the evaluation tab.

Throughput at 166 tok/s/user on Qwen 3.5 397B-A17B (B200): FP4 hits 1864 tok/s/chip, BF16 hits 660. Per-million costs land at $0.26 and $0.73 respectively. FP4 is 182% cheaper per token; FP4 delivers 182% more tok/s/chip. The cost-throughput tradeoff from lower precision is only part of the picture — see the evaluation page for accuracy data.

Toward the upper edge of the 59–272 tok/s/user interactivity band, at 219 tok/s/user on Qwen 3.5 397B-A17B (B200): FP4 runs 1014 tok/s/chip at $0.47/M tokens, BF16 runs 299 at $1.60/M. FP4 is 239% cheaper per token; FP4 delivers 239% more tok/s/chip. Precision changes affect both inference speed and model quality — consult the evaluation tab for accuracy benchmarks. (Numbers reflect the default 1k/1k selection for this URL — table and chart below update if you change sequence or model in the controls. Each side uses the best available serving configuration for that precision, which may include speculative decoding such as MTP where recipes exist — the same convention as the other comparison pages.)

Qwen 3.5 397B-A17B: FP4 versus BF16 throughput and cost at matched interactivity levels on B200
FP4 versus BF16 throughput and cost per million tokens on B200 for this comparison's canonical default workload.
Interpolated from real benchmark data. Edit target interactivity values below to compare at different operating points.
Metric
Interactivity (tok/s/user)
Interactivity (tok/s/user)
Interactivity (tok/s/user)
Throughput (tok/s/chip)
FP4:4730.7BF16:1216.1
FP4:1864.4BF16:660.2
FP4:1013.7BF16:299.5
Cost ($/M tok)
FP4:$0.102BF16:$0.395
FP4:$0.258BF16:$0.728
FP4:$0.474BF16:$1.605
tok/s/MW
FP4:2766489BF16:711170
FP4:1090275BF16:386094
FP4:592803BF16:175125
Concurrency
FP4:~199BF16:~49
FP4:~51BF16:~18
FP4:~5BF16:~6

Inference Performance

Agentic inference metrics from the AgentX scenario and fixed-sequence inference metrics across models, hardware configurations, and serving parameters.

Vendor:
Deployment:
Spec Decoding: