The CM2X512-5400C4PRO is a 512 MByte, two-rank DDR2 SDRAM DIMM designed for extreme speed. This part delivers outstanding performance in the latest generation of DDR2-based motherboards. It has been tested extensively in multiple DDR2 motherboards to ensure compatibility and performance at its rated speed. This memory has been verified to operate at 667MHz at the low latencies of 4-4-4-12.