Microsoft has released Windows Server 2012 and is letting businesses have a play with it for free for 90 days on the Azure cloud platform.

The main edition of Windows Server 2012 will ship in two versions. The first has virtualisation support and one without. The Datacentre version, which has it, costs $4,809, while the Standard edition, which does not, will cost $882.

There is an Essentials version, which replaces Small Business Server, for $501 per server, and Windows Server 2012 Foundation, which will only be available pre-installed on hardware.

Microsoft is hoping that helps drive SMBs to take up virtualisation. At the moment only a fifth of servers are virtualised, and that's mostly in large enterprises. However Redmond thinks that there are more SMBs who want to virtualise their servers they were just waiting for the price to fall. One of the new features in Windows Server 2012 is Hyper-V 3.0, a new hypervisor for virtualisation,