OS:

Windows XP, or
Windows Vista (32-bit; 64-bit versions of Vista are not supported)
CPU:

2.0GHz or higher, or AMD equivalent
RAM:

512 MB or more
Disk Drive:

8x or faster DVD drive for retail SKUs
Not required for digitally downloaded version
Hard Drive:

8.0 GB or more of free space
Video:

GeForce4, ATI Radeon 8500 or greater
Note: ATI Radeon 9200 and 9250 PCI, NVIDIA Geforce 4 MX cards are not supported.
Sound:

DirectX 9.0c compatible sound card
Network, Internet Multiplayer:

2 players (no voice support):
56 Kbps Internet connection
2-8 players (with voice transmission):
Broadband-class connection