Microsoft has opened up the beta programme for its forthcoming Windows Vista to the general public. 

The Windows Vista Beta 2 Customer Preview Program is available to download from the company's website or can be ordered on DVD. 

The Beta 2 version was released to developers at the WinHEC conference at the end of last month. 

Microsoft is warning that the operating system is still in development and " should not be used in a production environment or on a main machine in the home ". The software is also time limited and will cease to function after 1 June 2007.

The download version is only suitable for users with a fast internet connection; the 32-bit version is 3.5GB, while the 64-bit version weighs in at 4.4GB.

The pre-release software is Windows Vista Ultimate edition, which is the most feature-packed version of Vista.

To get the most out of Vista, Microsoft recommends running it on a 1GHz PC with at least 1GB of RAM and a 128MB graphics card capable of running the Aero graphical interface.

Click the link for the full Windows Vista specifications.