DTM68157-M is an Unbuffered 512Mx64 memory module, which conforms to JEDEC's DDR4- 2666V, PC4-2666V standard. The assembly is Single-Rank, comprised of eight Micron 512Mbx8 DDR4-2666V SDRAMs.One EEPROM is used for Serial Presence Detect.Both output driver strength and input termination impedance are programmable to maintain signal integrity on the I/O signals in a Fly-by topology.