Windows</br>XCOM: Enemy Unknown:</br>PC:</br>OS:Windows Vista </br>Processor:2 GHz Dual Core </br>Memory:2 GB RAM </br>Graphics:NVIDIA GeForce 8600 GT / ATI Radeon HD 2600 XT or greater </br>DirectX®:9.0 </br>Hard Drive:20 GB HD space </br>Sound:DirectX Compatible </br>Other Requirements:Broadband Internet connection</br>Additional:Initial installation requires one-time internet connection for Steam authentication; software installations required (included with the game) include Steam Client, Visual C++ 2008 Redistributable, DirectX and Microsoft .NET 4.</br>Sid Meier's Civilization V:</br>PC:</br>OS: Windows® Vista SP2/ Windows® 7 </br>Processor: Intel Core 2 Duo 1.8 GHz or AMD Athlon X2 64 2.0 GHz </br>Memory: 2GB RAM </br>Graphics:256 MB ATI HD2600 XT or better, 256 MB nVidia 7900 GS or better, or Core i3 or better integrated graphics </br>DirectX®: DirectX® version 9.0c </br>Hard Drive: 8 GB Free </br>Sound: DirectX 9.0c-compatible sound card </br>Note: Optimized for the touch-screen Ultrabook™ device</br>