These memory modules are 100% compatible with the xServe G5 systems and are in Kits of (2). If you have any questions regarding these modules or your system please feel free to contact us. APPLE Part# M9447G/A Compatible 1GB ECC PC3200 DDR DIMM KIT $140.00 APPLE Part# M9448G/A Compatible 2GB ECC PC3200 DDR DIMM KIT $280.00