Apple PowerMac G5 featuring dual 1.8 GHZ processors, 4.5 Gigabytes of RAM, 160 GB Serial ATA HardDrive, an additional 100 GB Serial ATA HardDrive. Airport extreme, 4x DVD Burner. Includes Apple USB keyboard and an Apple Mighty Mouse. Includes USB 2.0 and firewire ports (both 400 and 800) This is a great computer and is very fast. OS X 10.4.5 installed