HYNIX 4GB SERVER DIMM DDR3 PC10600 (1333) REG ECC 1.35 v 2RX8 240P 512MX72 256mX8 CL9 8k HMT351R7BFR8A-H9 Buying memory can be tricky. This module is typically is used in servers. If you are not sure if this is the correct part for your system, contact the seller. Provide the the make, model and/or service tag of your system or mother board, or the part number from your current RAM can be used to help verify compatible memory.