gpt-oss 120B — MI325X vs MI355X Performance per Dollar
Cost per million tokens of MI325X (AMD CDNA 3) versus MI355X (AMD CDNA 4) on gpt-oss 120B. 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.
MI325X: $0.28 per million tokens. MI355X: $0.03. Both at 81 tok/s/user on gpt-oss 120B, with MI355X 935% cheaper.
Around the middle of the 71–113 tok/s/user interactivity band — at 92 tok/s/user — MI325X runs $0.33 per million tokens on gpt-oss 120B while MI355X runs $0.03. MI355X is the cheaper choice by 945%.
On gpt-oss 120B at 103 tok/s/user, the per-million math comes out to $0.48 for MI325X and $0.04 for MI355X; MI355X delivers 1201% more output per dollar. (Numbers reflect the default 1k/1k · fp4 selection for this URL — table and chart below update if you change sequence, precision, or model in the controls.)
GPU pricing (owning hyperscaler): MI325X $1.28/GPU/hr · MI355X $1.48/GPU/hr. Source: SemiAnalysis Market August 2025 Pricing Surveys & AI Cloud TCO Model.
| Metric | Interactivity (tok/s/user) | Interactivity (tok/s/user) | Interactivity (tok/s/user) |
|---|---|---|---|
| Dollar per Million Tokens | MI325X:$0.282MI355X:$0.027 | MI325X:$0.331MI355X:$0.032 | MI325X:$0.480MI355X:$0.037 |
| Concurrency | MI325X:~19MI355X:~100 | MI325X:~26MI355X:~74 | MI325X:~15MI355X:~55 |
Inference Performance
Inference performance metrics across different models, hardware configurations, and serving parameters.