Microsoft Details Windows 8 on ARM

Microsoft's Windows 8 will run on ARM architecture in addition to PC that use traditional x86 chips, and the company has finally unleashed a host of details about how that will work.

Microsoft has issued some additional details about Windows on ARM, for which it uses the acronym €œWOA.€ The operating system on that architecture will play a vital part in the company€™s long-term strategy for tablets and other mobile form factors.

When the release version of Windows 8 appears sometime in late 2012, it will come on both ARM and x86 hardware. The operating system has been redesigned to operate with equal aplomb on traditional PCs and tablets: The start screen of colorful tiles linked to applications is eminently touchable (all the better for small, portable touch-screens), and paired to a desktop with all the requisite tools for power users.

Although Windows on ARM is an initiative meant to capture the tablet market, Microsoft is moving quickly to position WOA as equally capable of handling users€™ productivity needs. €œWithin the Windows desktop, WOA includes desktop versions of the new Microsoft Word, Excel, PowerPoint, and OneNote, code-named €˜Office 15,€™€ Steven Sinofsky, president of Microsoft€™s Windows and Windows Live division, wrote in a Feb. 9 posting on the corporate Building Windows 8 blog. €œWOA will be a no-compromise product for people who want to have the full benefits of familiar Office productivity software and compatibility.€

However, he also cautioned that €œWOA will not support any type of virtualization or emulation approach, and will not enable existing x86/64 applications to be ported or run.€ Virtualized or emulated software, apparently, will result in excessive consumption of system resources like battery life and CPU. €œIf you need to run existing x86/64 software, then you will be best serviced with Windows 8 on x86/64.€

In other words, for those who want to make a new WOA tablet their primary productivity platform, the combination of hardware and software could fit their needs, but those power users with a substantial amount of legacy software might want to acquire a system based on x86.

Those developers who wish to port existing apps onto WOA have a couple of options. €œMany apps will be best served by building new Metro-style front ends for existing data sources or applications,€ Sinofsky wrote, €œand communicating through a Web services API.€ Those best served by this approach include €œline-of-business applications and consumer Web properties.€

The other potential solution centers on €œreusing large amounts of engine or runtime code, and surround that with a Metro style experience,€ something he cautioned would take €œsome time.€

Microsoft has been working with a handful of ARM licensees, including Texas Instruments, Qualcomm and Nvida; in turn, these firms have been working with hardware manufactures on the creation of actual devices running WOA. Microsoft wants WOA devices to ship at the same time as PCs designed for Windows 8 on x86, and is apparently taking steps to clearly label the respective hardware so potential buyers can tell them apart.

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