The new PC2-6400 Vista Upgrade edition is optimized for perfect compatibility for those transitioning from Microsoft Windows XP to Vista. The OCZ Vista Upgrade series has gone through stringent testing with the full spectrum of Vista versions to deliver a perfect balance of memory performance and stability across the full range of applications. For gamers shifting to Vista and who prefer the performance of high speed memory, the PC2-6400 Vista Upgrade 2GB kit is the ultimate upgrade from 1GB of RAM ensuring the best possible gaming and productivity on Vista systems.