Virtual PC 2007 is the main competitor in the desktop virtualization space with long-time market leader VMware Workstation. Virtual PC 2007 is a free download, available at http://www.microsoft.com/downloads/details.aspx?FamilyId=04D26402-3199-48A3AFA2-2DC0B40A73B6. Here are notable highlights of Virtual PC 2007—along with notable failings.

10. Support for migrating from Virtual PC 2004 Service Pack 1 (SP1)—Virtual PC 2007 supports in-place upgrades from Virtual PC 2004 SP1. The virtual machine (VM) file format remains identical, but you’ll need to reinstall Virtual Machine Additions after you upgrade. If you’re running a version of Virtual PC other than Virtual PC 2004 SP1, you’ll need to uninstall the earlier version and then do a new installation of Virtual PC 2007.

9. No Linux guest support—A surprising limitation of Virtual PC 2007 is that it still doesn’t officially support running Linux as a guest OS. Although Linux actually does work on Virtual PC VMs—and Virtual PC 2007’s new hardware-assisted virtualization should improve performance over earlier releases—official support for Linux remains MIA.

8. Support for Windows Vista as a host—It’s probably no surprise that Virtual PC 2007 supports Vista as a host OS. Virtual PC 2007 runs on both 64-bit and 32-bit Windows Vista Business, Vista Enterprise, and Vista Ultimate editions, as well as on many earlier versions of Windows.

7. Support for Vista as a guest—The 32-bit versions of Vista can also run as guest OSs. Virtual PC 2007 supports the following guest OSs: Vista Business, Enterprise, and Ultimate editions; XP Pro and Tablet PC editions; Windows 2000 Professional; Windows 98 SE; and, for some reason, IBM OS/2 Warp 4.

6. Support for 64-bit host OSs—I mentioned earlier that Virtual PC 2007 supports the x64 editions of Vista as a host OS. Consequently, Virtual PC 2007 provides native 64-bit support for x64 architecture, which significantly increases the number of active VMs you can have by raising the 4GB memory limitation of 32-bit hosts to 16TB. Virtual PC 2007 also uses a different setup program for installation on 32-bit and 64-bit versions of Windows.

5. Unchanged management console—Continuing the ignoble tradition set by Virtual PC 2004, Virtual PC 2007 has one of lamest management consoles of all time. Although the Virtual PC 2007 management interface is Windows Aero–enabled, it still can’t hold a candle to the VMware Workstation interface.

4. No support for USB devices—Virtual PC 2007 lacks another feature that’s long been included in VMware Workstation products: support for USB devices. Virtual PC 2007 VMs can use USB mice and keyboards but can’t use other popular USB devices such as flash drives and other USB external storage devices.

3. Network-based installation of guest OSs—Another new feature is support for performing a Preboot Execution Environment (PXE) network boot. Virtual PC 2007’s PXE boot support enables Virtual PC 2007 VMs to be booted up from the network without needing to be pointed to a CD-ROM, DVD, or ISO image that’s stored locally.

2. Support for running VMs on multiple monitors—This cool feature lets you display different VMs on separate monitors. For example, using the multimonitor support, you can have Virtual PC 2007 run a VM in full-screen mode on one monitor while displaying the host OS on another monitor.

1. Support for hardware-assisted virtualization—One of the most important improvements in Virtual PC 2007 is its support for both Intel VT and AMD Virtualization hardware-assisted virtualization. Of course, the system that’s running Virtual PC 2007 must have a processor that possesses the new virtualization extensions.