Minimum: Supported OS: Microsoft Windows XP or Windows Vista (64 is supported) Processor: Pentium 4 3.2 Ghz, Pentium D 2.66 Ghz, AMD Athlon 64 3500+ or better Memory: 1 GB Graphics: 256 MB, Shader Model 3 required, NVidia 6800 or ATI X1650 or better* Hard Drive: 3.5 GB (Multiple saves and user created maps will increase the amount of needed hard disk space.) *Supported Video cards: NVidia 6800, NVidia 7000 series, 8000 series, 9000 series, 200 series. 8800M and 8700M supported for laptops. ATI X1650 – 1950 series , HD2000 series , HD3000 series , HD4000 series