Processor: 1.4GHz 64-bit
Disk Space: 32GB (Note: if your computer have over 16GB of RAM you will require more disk space)
Note that these are estimated system requirements. If your computer has less than the “minimum” requirements, you will not be able to install Windows Server 2012 correctly.
Actual requirements will vary based on your system configuration and the applications and features you install.
For more information refer to Microsoft Technet Documentation.