Windows 8 Developer Preview ISO [Direct Download Links]
Finally Microsoft made available Developer Preview of Windows 8 via its Windows Dev Centerfordevelopers, though this build is intended for end users you can still download Windows 8 developer preview ISO image and install over Windows XP/Vista/7.
System Requirements for Windows 8 Developer Preview
1 gigahertz (GHz) or faster 32-bit (x86) or 64-bit (x64) processor
1 gigabyte (GB) RAM (32-bit) or 2 GB RAM (64-bit)
16 GB available hard disk space (32-bit) or 20 GB (64-bit)
DirectX 9 graphics device with WDDM 1.0 or higher driver
Taking advantage of touch input requires a screen that supports multi-touch
Before Installing Developer Preview You need to perform clean install Developer preview with Developer Tools build in Windows XP/Vista/7, however you can keep accounts, files, settings by upgrading from Windows XP/Vista/7 to Windows 8 with the install of Developer preview build, best option is performing a clean install. Windows 8 Developer Preview Build available in ISO images format, you can download and burn them with built-in Windows Disc Image Burner in Windows 7.
Uninstalling Windows 8 Developer Preview
You can’t uninstall the Windows Developer preview , you need to reinstall your previous operating system.
Download links for Windows 8 Developer Preview
32-bit (2.8 GB)
64-bit (3.6 GB)