The ISA Doesn't Matter Where It Counts

# Summary The article argues that the CPU instruction set architecture (ISA)—whether x86 or Arm—matters far less than commonly believed in AI infrastructure, particularly in datacenter sockets closest to GPUs. The real value differentiators are coherent links between CPUs and GPUs (like NVLink), not the ISA itself, as evidenced by Nvidia's willingness to deploy CUDA on Arm-based Grace processors and opening NVLink to multiple ISAs through partnerships. As software moves closer to the GPU, the ISA becomes increasingly irrelevant since the bottleneck is bandwidth and integration rather than CPU instruction compatibility.