Only 2nd Generation Intel Xeon Scalable x2xx Processors support memory modules built with 16Gbit DRAM.
Memory will clock down to run at optimal speeds depending on processor model installed. See latest ProLiant QuickSpecs for processor models and supported memory speeds.
This system supports Registered ECC (RDIMM) or Load Reduced (LRDIMM) memory. Mixing RDIMM and LRDIMM is not supported within this system.