Minimum Specs (Required for playing Total War: Shogun 2):

* 2 GHz Intel Dual Core processor / 2.6 GHz Intel Single Core processor , or AMD equivalent (with SSE2)
* 1GB RAM (XP), 2GB RAM (Vista / Windows7)
* 256 MB DirectX 9.0c compatible graphics card (shader model 3)
* 1024×768 minimum screen resolution
* 20GB free hard disk space


Recommended Specs (Recommended for optimum game play of Total War: Shogun 2):

* 2nd Generation Intel? Core?i5 processor (or greater), or AMD equivalent
* 2GB RAM (XP), 4GB RAM (Vista / Windows7)
* AMD Radeon HD 5000 and 6000 series graphics cards or equivalent DirectX 11 compatible graphics card
* 1280×1024 minimum screen resolution
* 20GB free hard disk space

Minimum System Requirements for Empire
OS: Windows XP/Vista
Processor: Intel Pentium 4 @ 2.6 GHz / AMD Athlon XP 2600+
Memory: 1 Gb
Hard Drive: 15 Gb free
Video Memory: 256 Mb
Video Card: nVidia GeForce 7600 / ATI Radeon X1600
Sound Card: DirectX Compatible
Network: Broadband Internet Connection for Online Multiplayer
DirectX: 9.0c
Keyboard
Mouse
DVD Rom Drive

Recommended System Requirements
OS: Windows XP/Vista
Processor: Intel Core 2 DUO @ 2.2 GHz / AMD Athlon 64 X2 4400+
Memory: 2 Gb
Hard Drive: 15 Gb free
Video Memory: 768 Mb
Video Card: nVidia GeForce 8800 GTX / ATI Radeon HD 4830
Sound Card: DirectX Compatible
Network: Broadband Internet Connection for Online Multiplayer
DirectX: 9.0c
Keyboard
Mouse
DVD Rom Drive

http://www.gamesas.com/index.php?/topic/1118933-total-war-discussion/page__st__180__p__17385709__hl__total+war__fromsearch__1#entry17385709

Anyways, after a quick search online.