Windows 7's XP Mode needs 2GB RAM

By Ina Fried on 29 April 2009, 11:44am

Microsoft offered up a few more details on Tuesday on its once-secretive project to use virtualisation to offer an 'XP Mode' for Windows 7.

Microsoft is using its Virtual PC technology to allow Windows 7 users to run programs that work in XP but not in Vista. As far as technical requirements, XP Mode needs a beefier system than that required to just run Windows 7 or XP alone, including at least 2GB of memory and a system that has chip-level virtualisation from either Intel or AMD.

One of the challenges is that today it's often not that easy to tell whether your PC has such support. "Some PCs have it and some don't," said Scott Woodgate, a director in the Windows unit. "It's not as clear as it should be relative to which PCs have (hardware-based virtualisation) support and which don't."

At its core, XP mode consists of two things, the Windows Virtual PC engine and a licensed copy of Windows XP Service Pack 3 as a packaged virtual machine. Although neither piece will be included in the Windows 7 box, XP Mode will be a free download for those who have a licence to the Professional, Enterprise or Ultimate editions of Windows 7.

Microsoft is aiming XP Mode primarily at small businesses, Woodgate said. "That's a class of customers that may have Windows XP apps that they may want to run on Windows 7," he said.

One of the benefits of XP Mode over Microsoft's existing virtualisation products is the fact that, after a setup process, the Windows XP virtual machine runs in the background so users don't have to manage multiple desktops. XP Mode automatically installs shortcuts for XP programs in the Windows 7 start menu. The experience from that point on is similar to the one offered by VMware's Fusion and Parallels in their virtualisation products.

Woodgate noted that XP Mode isn't a security solution. Indeed, to protect their systems, users will need antivirus software running both on their Windows 7 desktop as well as a copy running inside their Windows XP virtual machine.

The beta version of XP Mode is debuting alongside the Windows 7 Release Candidate that is going to developers this week and being made publicly available on 5 May. Microsoft said a final release will depend on the feedback to the beta, but Woodgate said Microsoft hopes it can be ready for download at the same time Windows 7 is made broadly available.

Microsoft has been working on the XP Mode as long as it has been developing Windows 7, and Woodgate said even he is surprised it stayed secret for so long.