Hi,
Here are my specs. i can run it on high without or a little lag. 
Manufacturer: MSI 
Processor: AMD Sempron(tm) Processor 2800+, MMX, 3DNow, ~1.6GHz 
Memory: 1024MB RAM 
Hard Drive: 80 GB Total 
Video Card: NVIDIA GeForce 6200 
Monitor: Plug en Play-monitor 
Sound Card: Realtek AC97 Audio 
Speakers/Headphones: Logitech X530 
Keyboard: Logitech G15 (NEED MUCH RAM)
Mouse: Logitech HID-compliant G5 Laser Mouse 
Mouse Surface: Logitech G5 (NEED MUCH RAM)
Operating System: Windows XP Professional 
in total whit hardware its cost me € 1000,-
Greetz,
Eelkon