Transcend Transcend 4GB DDR3 1600 PC3-12800 240-pin DIMM ECC Registered CL11. Internal memory: 4 GB, Memory layout (modules x size): 1 x 4 GB, Internal memory type: DDR3, Memory clock speed: 1600 MHz, Memory form factor: 240-pin DIMM, CAS latency: 11, ECC