PC Download: Portal 2 for $15, Portal 2 - Two Pack for $27.5, Portal + Portal 2 Bundle for $17.49

o OS: Windows 7 / Vista / XP
o Processor: 3.0 GHz P4, Dual Core 2.0 (or higher) or AMD64X2 (or higher)
o Memory: 1GB XP / 2GB Vista
o Hard Disk Space: At least 7.6 GB of Space
o Video: Video card must be 128 MB or more and should be a DirectX 9-compatible with support for Pixel Shader 2.0b (ATI Radeon X800 or higher / NVIDIA GeForce 7600 or higher / Intel HD Graphics 2000 or higher).
o Audio: DirectX 9.0c compatible