Windows Server 2012 Beta Essentials [system requirement and download link ]

System requirements

CPU: 64-bit 1.4 GHz single core or 1.3 GHz multi-core (minimum) to 3.1 GHz multi-core (recommended) or faster processor.
Memory: 2 (minimum) to 8 (recommended) GB RAM or more
Disk: 160G disk space
Client OS: Windows 7, Windows 8, Mac OS X version 10.5 to 10.7