minimal:
reqprocessor: 2.2 GHz Dual Core CPU
reqgraphics: GeForce GT 750M / 9800GTX / Radeon HD 3xxx. OpenGL 3.2+
reqmemory: 4 GB RAM
reqdiskspace: 5 GB available space
reqsystem: Ubuntu 12 / Fedora 20 / Steam OS

recommended:
reqprocessor: 2.8 GHz Quad Core CPU
reqgraphics: 1GB NVIDIA GTX 460 / ATI Radeon HD 6850. OpenGL 4.x+
reqmemory: 4 GB RAM
reqdiskspace: 5 GB available space
reqsystem: Ubuntu 14 / Fedora 21 / Steam OS