Kingston HyperX Genesis 4GB 1866MHz DDR3 CL10 DIMM Desktop Memory KHX18C10/4 4GB Module of DDR3 Non-ECC Memory Utilizes HyperX module with faster latency timing for higher performance and speed Specifically designed and tested for compatibility in various makes and models of desktop computers From the industry leader in PC memory Non-ECC 1866MHz 240-pin CL10 Unbuffered DIMM Backed by a lifetime warranty and free technical support