Minimum requirements:

Processor:  2 GHz Dual Core
Graphic card:  Nvidia Geforce 8600 GT / ATI Radeon X 1800
(256 MB VideoRAM, DirectX 9c, Shader Model 3.0)
Memory:  2 GB RAM

Recommended requirements:

Processor:  Dual Core
Graphic card:  Nvidia Geforce 8800 GTX / ATI Radeon 3870
(512 MB VideoRAM, DirectX 9c, Shader Model 3.0)
Memory:  2 GB RAM