Minimum: Full Version of original Call of Duty, 3D hardware accelerator card required - 100% DirectX 9.0c compatible 32MB hardware T&L-capable video card and the latest drivers*, Microsoft Windows 2000/XP, Pentium III 800MHz or Athlon 800MHz processor or higher, 128MB RAM (256MB Recommended), 1150MB of uncompressed free hard disk space (plus 600MB for Windows 2000/XP swap file), 100% DirectX 9.0c compatible 16-bit sound card and latest drivers, 100% Windows 2000/XP compatible mouse, keyboard and latest drivers, DirectX 9.0c (included)
Multi-player Requirements:

Internet (TCP/IP) and LAN (TCP/IP) play supported
Internet play requires 56kbps (or faster) modem and latest drivers
LAN play requires network interface card and latest drivers

Important Notice: *Some 3D accelerator cards with the chipset listed here may not be compatible with the 3D acceleration features utilized by Call of Duty United Offensive. Please refer to your hardware manufacturer for 100% DirectX 9.0c compatibility.
Supported Chipsets

All ATI Radeon cards
All nVidia GeForce cards
Matrox Parhelia

Call of Duty: United Offensive videos