Microsoft has launched a site outlining the minimum hardware requirements for the next version of the Windows OS (operating system), Windows Vista.

The move comes less than a week before the company will host its WinHEC (Windows Hardware Engineering Conference) in Seattle. At the show, which starts on Tuesday, Microsoft and hardware manufacturers are expected to display the way Vista will run on a variety of machines, as well as showcase add-on technology built to enhance the OS.

On the Microsoft 'Get Ready' site, the company has outlined the requirements for running both low-end versions of Vista or higher-end versions that take advantage of the OS's Aero graphical user interface capabilities.

The company differentiates between the two by calling the former a 'Windows Vista Capable PC' and the latter a 'Windows Vista Premium Ready PC.'

Hardware requirements for a Vista Capable PC are a modern processor with a speed of at least 800MHz, 512MB of system memory and a graphics processor that is DirectX 9.0 capable.

A Windows Vista Premium Ready PC has a good deal more requirements. It must have at least a 1GHz 32bit (x86) or 64bit (x64) processor, 1GB of RAM, 128MB of graphics memory, 40GB of hard drive capacity with 15GB free space, a DVD-ROM drive, audio output capabilities and internet access capability.

It also needs a graphics processor that runs Windows Aero, which Microsoft defines as a DirectX 9.0 class graphics processor that supports a Windows Display Driver Model Driver, Pixel Shader 2.0 in hardware and 32 bits per pixel.

Microsoft began working with hardware partners several months ago to prepare customers for Vista's release. In April, PCs with stickers saying 'Windows Vista Capable' became available in stores, letting customers know what hardware can be upgraded to Vista once it is available. Microsoft does not plan to do the same with the Windows Vista Premium Ready designation, recommending customers ask a retailer or manufacturer about PCs that meet those requirements.