In order for you to play Assassin's Creed II on Windows with minimal graphics settings, your computer must meet the following requirements
OS *:
Windows® XP (32-64 bits) /Windows Vista®(32-64 bits)
*Processor (CPU):
Intel Core® 2 Duo 1.8 GHZ or AMD Athlon X2 64 2.4GHZ
Memory (RAM):
1.5 GB Windows® XP / 2 GB Windows Vista® - Windows 7®
Graphics Card:
256 MB DirectX® 9.0–compliant card with Shader Model 3.0 or higher (see supported list)
DirectX®:
DirectX 9.0
Hard Drive:
8 GB free space
Sound:
DirectX 9.0 –compliant sound card
Supported Peripherals:
Keyboard, mouse, optional controller
* This product does not support Windows® 98/ME/2000/NT
Supported Video Cards at Time of Release:
ATI® RADEON® X1950, HD 2000/3000/4000/5000 series NVIDIA GeForce® 7/8/9/100/200 series
In order to play Assassin's Creed II on Windows with maximum graphics settings, you need a computer with a configuration no worse than the following
OS *:
Windows® XP (32-64 bits) /Windows Vista®(32-64 bits)
*Processor (CPU):
Intel Core® 2 Duo E6700 2.6 GHz or AMD Athlon 64 X2 6000+ or better
Memory (RAM):
1.5 GB Windows® XP / 2 GB Windows Vista® - Windows 7®
Graphics Card:
GeForce 8800 GT or ATI Radeon HD 4700 or better
DirectX®:
DirectX 9.0
Hard Drive:
8 GB free space
Sound:
5.1 sound card
Supported Peripherals:
Keyboard, mouse, joystick optional (Xbox 360® Controller for Windows recommended)