Only Intel Xeon x2xx Series (Cascade Lake-SP) processors can use memory modules built with 16Gb density DRAM. BIOS/firmware updates and/or specific board revisions may also be required.
Maximum memory bandwidth is achieved by upgrading in groups of six per CPU. Utilizing the additional sockets for increased capacity, also known as split-channels, will reduce aggregated memory bandwidth (GB/s).
Faster memory will clock down to run at optimal speed depending on processor model installed.