16GB Total. 1pcs 16GB DDR4, 2133MHz, NON ECC, CL15, 2R, X4, 1.2V, , DIMM, 288-pin Brand Computer Memory Solutions LIFETIME WARRANTY BY Computer Memory Solutions Compatible with: Supermicro SuperServer 5019S-L (Super X11SSL-F) Supermicro SuperServer 5019S-M (Super X11SSH-F) HyperX for Supermicro SuperServer 5019S-M2 (Super X11SSZ-QF) Maximum Memory: 64GB 2133/1866/1600MHz ECC DDR4 SDRAM 72-bit, 288-pin (UDIMM) gold-plated DIMMs Expansions: Sockets 4 Important: Faster memory will clock down to run at optimal speed and voltage depending on processor model and number of modules installed. We recommends installing K4 kits for optimal quad channel performance configurations. Registered RDIMM and Load Reduced LRDIMM memory modules CANNOT be mixed within the same system. Mixing x4 and x8 modules is allowed, however not within the same bank.