AMD Instinct

AMD Instinct is AMD's line of data center GPU accelerators for AI and high performance computing (HPC), built on its CDNA architecture and programmed through ROCm software. The MI250X uses CDNA 2, the MI300X and MI325X use CDNA 3, the MI350X and MI355X use CDNA 4, and the MI455X uses CDNA 5. The MI355X is an Open Compute Project Accelerator Module (OAM). The MI455X is an Enhanced Accelerator Module (EAM) designed for AMD's Helios rack.

The MI355X carries 288 GB of HBM3E high bandwidth memory at 8 TB/s and lists a 1,400 W typical board power. It peaks at 2.5 petaFLOPS (PFLOPS) of FP16 matrix math without sparsity. The MI455X, with a launch date of July 23, 2026, lists 432 GB of HBM4 at 23.3 TB/s and 5 PFLOPS of FP16 matrix math. AMD specifies direct liquid cooling for the MI455X, where the MI355X page lists passive and active cooling.

A model whose weights and cache fit in 288 GB runs on one MI355X, and a larger one needs an MI455X or a split across GPUs. Before ordering, confirm that every library and custom CUDA kernel in the stack has a ROCm build.

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Last verified October 7, 2026.