HotHardware published AMD 5nm Zen 4 EPYC CPUs And Radeon Instinct GPUs To Power El Capitan Supercomputer A quote from the article:

AMD just announced today a design win in conjunction with the Lawrence Livermore National Laboratory (LLNL) and Hewlett-Packard Enterprise (HPE), win which it will be providing the hardware powering the El Capitan exascale-class supercomputer. What caught our eye about this announcement was not the compute performance -- which will be enormous.

  AMD 5nm Zen 4 EPYC CPUs And Radeon Instinct GPUs To Power El Capitan Supercomputer