http://www.bistudio.com/english/games/arma3
System requirements
Operating system: Windows 7 / Vista
Processor: Intel Core i5 or AMD Athlon Phenom X4 or faster
Memory: 2 GB
Video card: Nvidia Geforce GTX 260 or ATI Radeon HD 5770 with Shader Model 3 and 896 MB VRAM, or faster
DVD: Dual Layer compatible
Hard disk: 15 GB free space
Other: DirectX® 10