But remember thats not an actual list just an estimate.it's safe to say it'll be something like:
CPU: SSE2 compatible CPU.
RAM: XP = 1 GB, Vista/W7 = 2GB
GFX card: Nvidia 6600, ATI 1300 or higher ( Shader Model 3, 128MB VRAM and up )
those will of course not enable u to play on anything but low settings. But it's fairly safe to say that u will be able to start it.