This HP 840758-191 compatible 32GB DDR4-2666MHz dual rank registered ECC 1.2V 288-pin CL17 factory original RDIMM is 100% guaranteed to be compatible with your system and to work right the first time...
This HP 879527-091 compatible 16GB DDR4-2666MHz single rank unbuffered ECC 1.2V 288-pin CL19 factory original UDIMM is 100% guaranteed to be compatible with your system and to work right the first...