Intel or AMD Single-Core Prozessor (2,0 GHz) or better
Memory
2 GB or more
Graphics
Radeon HD, Geforce 8800GT (Shader 3.0 and 512 MB RAM)
DirectX®
DirectX 9.0c or OpenGL
Hard Drive
8 GB
Sound
DirectX comp. Stereo Sound Card
Other
Internet connection with 6.000 BPS or more for Multiplayer recommended
Go to: http://store.steampowered.com/ and download STEAM client
Click "Install Steam" (from the upper right corner)
Install and start application, login with your Account name and Password (create one if you don't have).
Please follow these instructions to activate a new retail purchase on Steam:
Launch Steam and log into your Steam account.
Click the Games Menu.
Choose Activate a Product on Steam...
Follow the onscreen instructions to complete the process.
After successful code verification go to the "MY GAMES" tab and start downloading.