Rogueware 4GB DDR4 2666MHz Value UDIMM Desktop Memory Module (RVR2666C19LD4GB) - Module Size: 4GB, Module Type: Long DIMM, Memory Speed: 2666MHz, Cache Latency (CL IDD): 19 Cycles, Row Cycle Time: 45ns, Refresh to Active Time: 350ns, Voltage: 1.2 Volt, Operating Temperature: 0°C to +85°C