Minimum System Requirements
Windows
OS:
Windows XP (Service Pack 2) or Windows Vista (Service Pack 1)
Processor:
(XP) 2.0 GHz P4 processor or equivalent; (Vista) 2.4 GHz P4 processor or equivalent
Memory:
(XP) 1 GB; (Vista) 1.5 GB
Graphics:
128 MB Video Card with support for Pixel Shader 2.0
Storage:
At least 6.5 GB of hard drive space with at least 1 GB additional space for custom content
These are the requirements the publisher lists on Steam.
