If your wondering about vista memory this is a little bit info.
All editions of Windows Vista 64-bit provide increased memory support beyond the standard 4 gigabytes available with 32-bit editions. Refer to the specific edition of Windows Vista 64-bit to determine maximum memory capacity.
Windows Vista Edition.....64-bit memory support
Home Basic...................8 GB
Home Premium.............16 GB
Ultimate.......................128+ GB
Business.......................128+ GB
Enterprise.....................128+ GB