HP Compaq 8GB 1Rx4 PC3-12800R-11 Kit 8 DDR3 1600 647899-B21 HP 8GB 1Rx4 PC3-12800R-11 Kit - 8 GB (1 x 8 GB) - DDR3 SDRAM - 1600 MHz DDR3-1600/PC3-12800 - ECC - Registered - 240-pin - DIMM HP 8GB 1Rx4 PC3-12800R-11 Kit 8 GB (1 x 8 GB) - DDR3 SDRAM - 1600 MHz DDR3-1600/PC3-12800 - ECC - Registered - 240-pin - DIMM