Left 4 Dead 2

Minimum Requirements : 

Operating System: Windows 7 / Windows Vista / Windows Vista64 / Windows XP
Processor: Intel Pentium 4 3.0 GHz
Memory: 1 GB for XP / 2GB for Vista
Hard Drive: 7.5 GB Free
Video Card (graphics): DirectX 9 compatible video card with 128 MB, Shader model 2.0. ATI X800, NVidia 6600 or better
DirectX: 9.0c
Sound Card: DirectX 9.0c compatible sound card

Link Download : Click Here (Torrent)

You Must Have : Torrent, PowerIso, Daemon Tools