About Hydrophobia: Prophecy

Minimum:
* Windows XP, Vista, or 7
* Core 2 Duo or Athlon X2 CPU
* 2 GB RAM
* 512 MB VRAM
* GeForce 8600 GT or Radeon HD 3650 GPU
* 8 GB HD space

Steam installation only uses 5.6 GB HD space, so the overestimate probably includes space for page file and saves.