Min. Specification
CPU - Pentium 3 800MHz or higher
RAM - 256MB
VGA - 3D speed over GeForce2 or ATI 9000
SOUND - DirectX 9.0c Compatibility card
HDD - 4GB or higher(including swap and temporary file)
OS - Windows 2000, XP, Vista
Required Specification
CPU - Pentium 4 2.4GHz or higher
RAM - 512MB
VGA - 3D speed over GeForce FX 5600 or ATI9500
SOUND - DirectX 9.0c Compatibility card
HDD - 4GB or higher(including swap and temporary file)
OS - Windows 2000, XP, Vista
Taken from the official website