Compaq Presario Media Center SR2013WM Desktop PC Athlon 64 3800+ at 2.4 GHz 160 GB SATA 7200RPM Hard Drive, 16X DVD(+/-)R/RW RAM Optical Drive, Compaq Keyboard and Mouse, Productivity Software Bundle, 250 Watt Power Supply Upgraded to Microsoft Vista Home operating system w/COA and includes Windows XP Media Center Edition 2005 w/COA pre-loaded as a backup copy on second hard drive partition. XP can also be installed for a dual boot operating system! Motherboard Features: Utilizes Dual Channel Memory with stock 512 MB DDR2 SDRAM PC2-4200 MB/sec (or 2 GB maximum upgrade) Integrated Nvidia GeForce 6150 LE video chip, Integrated Realtek ALC888 High Definition 8 channel audio, Integrated 10/100Mb/s 10 Base-T Ethernet Networking Interface and 56K PCI Modem. Micro-ATX Style Asus A8M2N-LA Motherboard using an AMD Athlon 64 3800+ processor at 2.4 GHz with Front-side bus at 2000 MegaTransfers/second. Motherboard Expansion Slots: Three PCI and One PCI Express x16 graphics