A couple of notes. You will see that installing the Steam client is a requirement for playing the game. Also while the minimal requirements use DirectX 9, the recommended specs have the game running with DirectX 11 for some extra eye candy.
Minimum System Requirements
Operating System: Windows XP SP3/ Windows Vista SP2/ Windows 7
Processor: Dual Core CPU
Memory: 2GB RAM
Hard Disk Space: 8 GB Free
DVD-ROM Drive: Required for disc-based installation
Video: 256 MB ATI HD2600 XT or better, 256 MB nVidia 7900 GS or better, or Core i3 or better integrated graphics
Sound: DirectX 9.0c-compatible sound card
DirectX: DirectX version 9.0c
Recommended System Requirements
Operating System: Windows Vista SP2/ Windows 7
Processor: 1.8 GHz Quad Core CPU Memory: 4 GB RAM
Hard Disk Space: 8 GB Free
DVD-ROM Drive: Required for disc-based installation
Video: 512 MB ATI 4800 series or better, 512 MB nVidia 9800 series or better
Sound: DirectX 9.0c-compatible sound card
DirectX: DirectX version 11
Other Requirements: Initial installation requires one-time Internet connection for Steam authentication; software installations required (included with the game) include Steam Client, Microsoft Visual C++2008 Runtime Libraries and Microsoft DirectX.



downloand civilization v here:
http://nogamer.blogspot.comPosted at 1:17PM on Oct 5th 2010 by hichamos