Well, besides the obvious possibility of, "They're wrong," It seems like they are looking for a single vendor to supply CPU and GPU for these builds. Also, you would need an ARM SOC with a ton of I/O -- lots of PCIe lanes, etc. The only one that seems to fit that bill is this just recently announced. AMD is likely using Infinity Fabric to directly link the CPU/GPUs here (almost a guarantee with them saying it is unified memory across the CPU and GPU) -- so you would need an ARM vendor to have interoperability with either their own GPU's (which don't exist for this application currently) or another vendor (AMD, Intel, Nvidia) and it's special coherent link.Silly question, but with the ARM supporters maintaining they have better IPC and use less power, why would the fastest supercomputers in the world all use x86 processors ? (AMD/Intel)
Since supercomputers use their own proprietary OS and applications, they should work on any selected hardware.