Microsoft will make at least four different versions of Windows 8 for devices with ARM processors, but you won't be running older Windows apps on any of them, according to an Intel executive. Renee James, Intel's senior vice president and general manager of Software and Services Group, also reaffirmed that Windows running on ARM devices will be focused on tablets and other mobile devices, according to Bloomberg.

Version Fatigue

If you thought Microsoft produced too many versions of Windows 7 or Vista, it sounds like you haven't seen anything yet. It's too early to know for sure how Microsoft will package Windows 8, but it's unlikely the company will give up on offering six different of its trademark OS as it has with both Windows 7 and Vista. Add to that version mix four variations for ARM tablets and possibly netbooks, and you've got a recipe for confusion for the non-techie consumer.

Legacy Apps

Since ARM's architecture is different from Windows' x86 roots with Intel, it's not surprising that legacy apps wouldn't be available on the new devices. But legacy issues are usually a bigger problem for businesses than home users. So unless you're hoping to run Microsoft Word 2007 on an ARM-based netbook, you may not have to worry too much. Enterprises, on the other hand, may be less likely to use an ARM-based version of Windows if they have custom-designed legacy software; however, it's also possible third parties would come up with a legacy emulator for ARM devices if Microsoft doesn't.

ARM vs. x86

James said Intel isn't worried about competing against another chip design in the Windows universe -- basically Intel's exclusive turf for the past 20 years. Intel's x86 architecture will support both new and old Windows programs on Windows 8, and run on everything from Windows-based mobile devices to televisions and PCs, according to the Register.

Intel also knows it can't depend on Microsoft and the PC to guarantee the chipmaker's future. Intel chief executive Otellini recently said his company had overhauled its roadmap to meet the growing demand for mobile devices such as tablets and smartphones. Despite the popularity of its Atom chips for netbooks, Intel's current processors are considered too power hungry to guarantee the long battery life that newer mobile devices require. ARM processor designs, on the other hand, are being used on a variety of mobile devices such as Apple's iPad and iPhone as well as numerous Android devices.

It's not clear what Microsoft has in store for Windows 8, but current rumors suggest Windows 8 for mobile devices will include an interface based on elements of Windows Phone 7's Metro UI.

Microsoft in April demoed an early version of Internet Explorer 10 running on an ARM device.

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