16GB DDR4-2666-MHz Rdimm/PC4-21
Cisco Systems Part# HX-MR-X16G1RS-H=
RAM Modules – RAM Module - 1.20 V Memory Voltage - DDR4-2666/PC4-21300 - DDR4 SDRAM - CL19 - 16 GB Memory Size - DIMM - 2666 MHz Memory Speed - Server - ECC - 288-pin Pins - Registered - Cisco HyperFlex HX220c M5 ...
16GB DDR3-1866MHZ Rdimm TAA
Cisco Systems Part# UCS-MR-1X162RZA++=
RAM Modules – TAA Compliant – RAM Module - 1.50 V Memory Voltage - DDR3-1866/PC3-14900 - DDR3 SDRAM - 16 GB Memory Size - DIMM - 1866 MHz Memory Speed - Server - Registered - Cisco UCS C220 M3 High-Density Rack Server