Cisco 4GB DDR3 SDRAM Memory Module - 4 GB - DDR3-1600/PC3-12800 DDR3 SDRAM - 1600 MHz - 1.35 V - ECC - Registered - 240-pin - DIMM

Up to 1600 MHz speed with Registered signal for smooth computer performance 4 GB memory allows you to have more programs open at a time DDR3 SDRAM interface synchronizes electrical and clock signals for an efficient data transfer rate