The Cosair XMS2 Extreme Performance DDR2 CM2X2048-6400C5 is a high-performance memory module designed for computers that require fast and reliable processing. With a total capacity of 4GB split into two 2GB modules, this DDR2 RAM operates at 800MHz with a PC2-6400 bus speed. Manufactured by Corsair in the United States, this DIMM module is known for its quality and stability, making it a popular choice for enthusiasts and professionals looking to upgrade their computer's memory capacity.