HP Pavilion Slimline Desktop PC - AMD E1-2500 (1.40 GHz) / 4GB Memory / 500GB Hard Drive / AMD Radeon HD 8240 / DVD&plusmn;RW/CD-RW / Windows 8.1 64-bit AMD E1-2500 APU (1.4 GHz) with Integrated AMD Radeon HD 8240 graphics Built-in 2.4GHz 1x1 high-speed wireless LAN (802.11b/g/n) 4GB PC3-10600 DDR3 SDRAM (expandable to 16GB),500GB Serial ATA hard drive (7200 rpm) SuperMulti DVD Burner drive,7-in-1 multimedia card reader Microsoft Windows 8.1 64-bit operating system preinstalled,HP USB keyboard andHP USB optical mouse