OS: Windows 8, Windows 7, Windows Vista, Windows XP Processor: Intel Core 2 Duo E6600 @ 2.40 GHz/AMD Phenom X3 8750 @ 2.4 Ghz Memory: 2 GB RAM Graphics: GeForce 8800 GT series with 512 MB RAM or ATI Radeon HD3870 with 512MB RAM DirectX: Version 9.0c Network: Broadband Internet connection Hard Drive: 5 GB available space Sound Card: DirectX® 9.0c or later Compatible Card Additional Notes: Internet connection for Steam activation and multiplayer functionality.