Windows 8 Professional is already to use, although it can't be activated before you buy product key windows 8 pro or activation crack have been published. Windows 8 is an operating system very fast and reliable than Windows 7.

Product key Microsoft Windows 8 Default:
Professional = XKY4K-2NRWR-8F6P2-448RF-CRYQH – Retail Key
Professional WMC = RR3BN-3YY9P-9D7FC-7J4YF-QGJXW – Retail Key for Windows Media Center.


System Reqirements :
• Processor: 1 gigahertz (GHz) or higher.
• RAM: 1 GB for 32-bit or 2 GB for 64-bit version.
• Hard disk free space: 16 gigabytes (GB) on 32-bit or 20 GB for 64-bit version.
• Graphics adapter: Microsoft DirectX 9 graphics device with WDDM.
• To use the sensory capabilities requires a tablet or a monitor that supports multitouch.
• To gain access to Windows shops need an active internet connection and a minimum screen resolution of 1024 x 768 pixels.
• To bind an application requires a minimum screen resolution of 1366 x 768.
• Internet access.

source : http://mastergomaster.com/windows-7-xp-8-vista-2012/windows-8-professional-retail-rtm-64-bit-32-bit/