AMD MI355X Takes on DeepSeek V4.1 Flash with Promising Results

Benchmarking AMD's MI355X in DeepSeek V4.1 Flash

AMD finally has a seat at the table in one of AI's more practical benchmarks. Artificial Analysis has added the AMD Instinct MI355X to AA-AgentPerf, with results reported on October 14, 2026.

What the Benchmark Actually Measured

The MI355X is built on AMD's CDNA 4 architecture. Each GPU carries 288 GB of HBM3E memory running at 8 TB/s, and the chip can draw up to 1,400 W. Artificial Analysis tested the accelerator on a single 8-GPU node. The setup ran ROCm nightly builds, AMD's software stack in its freshest and least settled form, alongside developmental versions of AVM technologies.

The Numbers: Close on Speed, Behind on Efficiency

According to Artificial Analysis, the MI355X posted output speeds on DeepSeek V4.1 Flash that rival Nvidia's Blackwell systems. It slipped slightly behind at higher concurrency, meaning when many users hit the system at once. Efficiency is where the gap shows. The MI355X delivered approximately 128 million tokens per second per megawatt at a rate of 100 tokens per second per user.

What This Means for the AI Hardware Race

For data center operators, the split result is useful information. Which chip wins depends heavily on which model you run and how many users you serve at once. The software story deserves close watching. These results came from ROCm nightly builds and developmental tooling. The research findings say further developing technologies are expected to enhance the MI355X's capabilities.

Conclusion

Nvidia still holds the efficiency crown on the lighter workload. AMD, for its part, has shown that on the right model at the right load, its memory-heavy design can beat the B200 outright.