If classic games stir your gaming genes, Windows isn't always the most congenial environment for yesterday's hits. From audio and graphics issues to freeing up conventional memory for MS-DOS, Windows XP (and Windows Vista) need some help in running older games. Thanks to virtualization, you can run classic operating systems and the games that made them great inside a window.
Virtualization has been around for awhile as a way to enable a single system to host one or more guest operating systems. Support and management personnel love it because they don't need to reboot to run an older version of Windows to provide help to a user stuck with legacy hardware or software. Now, thanks to Microsoft's decision to make Virtual PC 2007 free, you can try virtualization free for work - or play. You need Windows XP Professional (including x64 Edition) or Tablet PC Edition (including x64 edition) or Windows Vista Ultimate (32 and 64-bit versions) or Windows Server 2003. Get it here . It's a 30MB download, so it won't take long.
To use Virtual PC 2007, you need a spare copy of an older operating system that you can install into a virtual machine you create with Virtual PC 2007. I'm an OS packrat, so I still have old Windows CDs and floppy disks no longer in use on a system, and a copy or two of MS-DOS. I've used Virtual PC 2007 to create virtual machines running Windows 98 and even (wait for it….) MS-DOS 6.22! Although Virtual PC 2007 doesn't officially support MS-DOS, it will work. If you want to run a DOS game, but don't have any MS-DOS disks, grab a copy of http://www.freedos.org/ .
A virtual machine (VM) uses two system resources: a chunk of your hard disk space and some system RAM. If you want to run a VM along with other programs, having 2GB or more installed RAM is a good idea. When you set up a VM, you specify how much disk space to use and use the guest operating system's utilities to prepare the VM for use. It seems weird to run the DOS command 'format' inside a VM, but don't worry: you're only formatting the disk space reserved for the VM. The VM is stored on your hard disk as a file with the .vhd extension.
To learn more about installation and use, read the Virtual PC 2007 Release Notes in your browser. The Virtual PC Guy's Weblog is also a helpful resource. For example, you can set up a Virtual PC DOS application that runs from a command line in Windows : users don't need to know anything about virtualization to use it – a perfect solution for making a retro game available to anyone whose eyes glaze over when you say "virtualization."
After you install the operating system into the virtual machine, install the programs you want to use and run them normally. If you're planning to do some gaming in MS-DOS 6.22, you will need to crack open an old DOS manual to learn how to free up conventional memory (memory under 1MB) inside the VM with drivers such as EMM386.EXE or commands such as DOS=HIGH, UMB. You can also see Knowledge Base article 134399 for help, or use the MEMMAKER.EXE utility included in MS-DOS 6.22.
Does virtualization work? You bet! I was able to play Sierra's Red Baron, one of the best classic WWI dogfighting games ever written for MS-DOS (and a notorious memory hog that was impossible to run under Windows XP or Vista) within an MS-DOS virtual machine with full sound effects (keep in mind that your audio support may vary from game to game). If you prefer to run older Windows versions, Virtual PC 2007 is up to the task as well.
Virtual PC 2007 isn't perfect: it doesn't support USB storage devices (although it will access programs on CDs if you install the appropriate device drivers) and needs lots of RAM to provide good performance, but it's free – and fun – to try. Other virtualization environments you can try free include VirtualBox and DOSBox . VMWare also offers some virtualization products free of charge , but not its flagship VMWare.