The idea of running Windows on the Apple Computer hardware just got a lot more appealing with the introduction of Macs built on Intel processors. But don't expect the Cupertino, California, company, to be too keen on its users running Windows on the new machines.

Apple introduced two new Intel-based machines, an iMac desktop and the MacBook notebook, at MacWorld. The iMac is available now, with the MacBook scheduled to ship in February but available for ordering on Tuesday.

Even without specific help from Apple, the existence of Macs built on Intel's x86 instruction set eventually will give users a choice of OSes to run on their new Apple machines. Analysts believe it won't be long before someone comes up with a version of Windows that runs natively on the new Intel-based Macs, even despite a firmware incompatibility issue that prevents Microsoft's operating system from running on the new Intel-based Macs.

Apple's Intel-based Macs support extensible firmware interface (EFI), whereas Microsoft's Windows XP supports BIOS, and the two are not natively interoperable. EFI and BIOS control the basic functions a computer can do, such as start up and boot up the OS, without accessing programs from its hard drive.

"I have no doubt that a clever person would figure out how to make it work even if Apple doesn't support that," says Dan Kusnetzky, program vice president at IDC. "I've been amazed at how people have looked at vendor choices and found a way to do what they wanted to do anyway."

Looking at Linux

Linux also is a potential option for users that want to have more than one OS on their new iMac or MacBook, says Bruce Perens, vice president of Seattle-based SourceLabs, an open-source software and services company.

There are already Linux distributions, such as Yellow Dog Linux, designed for the Mac PowerPC architecture, he says, adding that it's only a matter of time before someone comes up with a version of Linux for the Intel-based Mac platform. "It probably just needs to be tested and tweaked slightly," he says.

In fact, if someone had the desire, they could run the Mac OS, Windows, and Linux simultaneously on one of the new Macs, Perens says. "If we take this to its conclusion, you could have three OSes running on these machines at once," he says. "Only a geek would want to do it, but it would be fun."

Before anyone gets too excited by the potential of multiple-OS Macs, they should remember that the issue of support is a critical one, Kusnetzky says. One benefit of having a computer that runs multiple OSes is that it removes the need for corporate users to install two machines on their desks, in order to run both Mac and Windows applications. But enterprise users tend to shy away from running an OS on a machine without some kind of vendor support, he says. "That begs the issue of who will support it once [Windows] is running," Kusnetzky says.

According to Microsoft, there's nothing that precludes Apple from certifying and supporting Windows on the Mac now that it is an industry standard-based hardware company.

"Just like all of Microsoft's OEMs, Apple can build industry-standard hardware that is compatible with Windows; Microsoft has an open specification and a process for certifying the hardware," a Microsoft spokeswoman from the company's public relations firm Waggener Edstrom says via e-mail. "Microsoft... would support Apple the same way it supports every other PC manufacturer."

Apple spokesperson Teresa Weaver confirms via e-mail that Apple has no plans to sell or support Windows, but says the company is doing nothing in its hardware design to preclude their systems from running Windows.

A Virtual OS

Mac users have been able to run Windows applications on their Macs for some time through emulation software, including a Microsoft product called Virtual PC. Microsoft plans to update that product to run on the new Intel-based Apple machines, but has not disclosed when.

The problem with running Mac applications on Windows through emulation has been one of performance, says John Czlonka, president of IEmulator.com, based in Edmonton, Canada. IEmulator is software that enables Windows applications to run alongside Mac applications on Apple hardware, and will have a new version for the Intel-based machines by the end of February.

"The biggest bottleneck to performance has been in translating code meant for PCs to the PowerPC processor on the Mac," he says. "Every emulation solution has run at a fraction of the speed of native code because of this."

The introduction of Intel-based Mac hardware should make the emulation of Windows applications on the Mac a lot easier and faster, he says. With Mac moving to Intel processors, the step of translating code can be skipped, and native PC code also can run natively on the Mac at the speed it is meant to run, Czlonka says.

Robert McMillan of the IDG News Service contributed to this article.