Why Multiboot?

In today's world of advanced operating systems and low hard disk prices, it certainly is not uncommon for many users to want to experiment with different operating systems. The world of consumer computing is ripe with many different options. With the proliferation of the Internet and its accompanying high-bandwidth needs, whole operating systems are available for free download, in particular numerous versions of the UNIX and Linux operating systems.

Along with just plain curiosity and experimentation, there are some other good reasons for wanting to switch between operating systems:

• Many users use two or more operating systems because of application compatibility issues. Hardware support issues arise too: Windows 98 might have drivers for old hardware that Windows XP doesn't support. And, I know people who still have to use some old and esoteric hardware devices that work only under MS-DOS.

• Some users want to run specific applications or games in the optimal environment.

• A developer might swap between Windows XP Professional and Windows 9x or NT 4.0 to test application compatibility.

• Web site developers need to use different OS versions to see how their pages look with the corresponding different Web browser versions.

• As an author, I need several operating systems functioning on a single computer to meet my testing and writing needs.

Other than buying multiple computers, there are two ways of accommodating these needs. You can multiboot, that is, select your desired operating system at bootup time. Or, you can run another operating system in a "virtual" computer; that is, in a special application program that lets the alternate OS think it's running on a PC of its own. The "virtual" approach is very useful, and we'll cover it later in the chapter.

NOTE

You should read, or at least skim, this entire chapter before beginning to implement a complex multiboot arrangement. We have not reiterated some considerations under each scenario. Pay particular attention to the issues of file formats, as well as applications and data sharing between operating systems. Then be sure to see "Tips from the Windows Pros: Living with More Than One OS" at the end of the chapter, which covers third-party multiboot solutions.

And although this chapter provides some solid fundamentals, an in-depth discussion of the topic couldand in fact doesfill an entire book. For additional details on setting up multiboot scenarios, we recommend that you pick up a copy of The Multi-Boot Configuration Handbook, published by Que.

Windows XP Professional directly supports multibooting with the following operating systems:

• Windows XP Home Edition

• Windows 2000 Professional

• Windows NT 3.51 or Windows NT 4.0

• Windows 95, Windows 98 and Me

• Windows 3.1 or Windows for Workgroups 3.11

• MS-DOS

• OS/2

Multibooting with UNIX and Linux is also possible, although it takes some extra effort.