Microsoft Windows 8: Hardware requirements & Availability

Hardware Requirements for Windows 8 Release Preview-

• Processor: 1GHz(GigaHertz) of Faster
• RAM(Random Access Memory): 1GB(Gigabytes) for 32bit and 2GB for 64bit
• HDD(Hard Disk Space): 16GB for 32bit and 20GB for 64bit
• Graphics Card: Microsoft DirectX 9 graphics Device with WDDM(Windows Display Diver Model) Driver

Additional Requirements-

• To use touch, You need a Tablet or a Multitouch supported Monitor.
• An active Internet connection is need to Access the Windows Store, to Download, to Run apps and needs a screen resolution at least 1024 × 768 as well.
• Internet access fees (ISP) might be apply.
• To use Snap apps, you need a screen resolution of at least 1366 × 768.

Microsoft Corporation released the Developers Preview (build 8102) of Windows 8 on September 13, 2011. The Consumer Preview(build 8250) on February 29, 2012. And Release Preview(build 8400) on May 31, 2012.
And hopefully Microsoft Windows 8 will be available from the last week of October, 2012.