Steam OS Installer

Valve has released the first public version of SteamOS, offering the promised chance to check out their game-centric Linux fork. A new SteamOS FAQ has all you need to know about this, and it seems advisable to remember their earlier warning that a comfort level with Linux is advisable before playing with this. The first version (SteamOS 1.0) is called 'alchemist' and it is based on the Debian 'wheezy' (stable 7.1) distribution.

What are the SteamOS Hardware Requirements?

Intel or AMD 64-bit capable processor
4GB or more memory
500GB or larger disk
NVIDIA graphics card (AMD and Intel graphics support coming soon)
UEFI boot support
USB port for installation

FAQ
Alternative install guide