Kimi K3 2.8T — B300 vs MI355X Performance per Dollar
Cost per million tokens of B300 (NVIDIA Blackwell) versus MI355X (AMD CDNA 4) on Kimi K3 2.8T. Owning-hyperscaler TCO normalized by output tokens — performance per dollar across LLM workloads. Pick the more cost-efficient SKU at every target interactivity level. Use the chart controls below to switch sequences, precisions, and metrics — same interactions as the main inference chart.
AgentX replays real coding-agent sessions rather than fixed-length prompts, so context grows turn over turn and most of each request is served from cache instead of being recomputed. That turns the comparison into a systems question: KV transfer between nodes, prefix-aware routing, and cache capacity all move the curve alongside raw chip throughput. Fixed-sequence workloads stay the clean baseline for kernel and silicon performance, so the two scenarios answer different questions about the same hardware. Learn more about AgentX →
Near the low end of the 19–112 tok/s/user interactivity band — at 42 tok/s/user — B300 runs $0.09 per million tokens on Kimi K3 2.8T while MI355X runs $0.11. B300 is the cheaper choice by 15%.
On Kimi K3 2.8T at 66 tok/s/user, the per-million math comes out to $0.12 for B300 and $0.16 for MI355X; B300 delivers 31% more output per dollar.
At 89 tok/s/user on Kimi K3 2.8T, B300 costs $0.15 per million tokens; MI355X costs $0.23. B300 is 55% more cost-efficient at this operating point. (Numbers reflect the default agentic-traces · fp4 selection for this URL — table and chart below update if you change sequence, precision, or model in the controls.)
Chip pricing (owning hyperscaler): B300 $2.26/chip/hr · MI355X $1.50/chip/hr. Source: SemiAnalysis Market July 2026 Pricing Surveys & AI Cloud TCO Model.
| Metric | Interactivity (tok/s/user) | Interactivity (tok/s/user) | Interactivity (tok/s/user) |
|---|---|---|---|
| Dollar per Million Tokens | B300:$0.094MI355X:$0.108 | B300:$0.124MI355X:$0.163 | B300:$0.146MI355X:$0.227 |
| Concurrency | B300:~12MI355X:~8 | B300:~8MI355X:~5 | B300:~6MI355X:~2 |
Inference Performance
Agentic inference metrics from the AgentX scenario and fixed-sequence inference metrics across models, hardware configurations, and serving parameters.