Windows 8 Start Menu

Windows 8 will be the first desktop operating system from Microsoft to support microprocessors with both x86 and ARM architectures. This week at the company’s Build conference for developers, Microsoft has been showing off laptop, desktop, and tablet computers with both x86 and ARM chips, and talking about how many of the new features in the operating system will work on both platforms — as will many apps. For instance, the company gave a demo of Microsoft Office running on a device with an ARM processor.

But while developers should be able to write new Windows 8 apps that are equally at home on ARM and x86 hardware, Microsoft says that apps explicitly developed for x86 platforms will not support Windows 8 running on an ARM device. This confirms what we’d heard earlier this year.

In other words, if you pick up a tablet, laptop, or other product with an NVIDIA Tegra 3 Kal El quad-core processor next year, it may be fast, light, and offer great battery life. But it might not run all of your favorite Windows app which you’ve been using since you bought your first Windows 95 computer.

In the future, developers will be able to write apps using any of the development tools supported by Microsoft, including HTML5, Silverlight, JavaScript, C, C++, C#, and VB and choose whether to support x86, ARM, or both. I suspect many of the new apps written for Windows 8 will work out of the box no matter what kind of processor you have. And many popular Windows apps that are under active development will also likely be updated to support ARM.

But there are thousands, if not millions of apps available for Windows that may never be updated — and most of them will never work on a computer with an ARM-based chip.

Many Linux-based operating systems can already run on x86, ARM, or other chip architectures. But since many third party apps that run on Linux are open source, there are tools which allow anyone to recompile an x86 app to work with ARM. That won’t be the case with Windows apps, since the percentage of open source Windows apps is much lower.

It will be up to developers to do the legwork and make sure their apps support Windows 8.

The loss of backward compatibility might be a big problem… but it also might not. On the one hand, one of the greatest strengths of the Windows platform is the fact that it’s been the dominant OS for so long that the vast majority of desktop software developed over the last 20 years has been developed to run on Windows.

On the other hand, most people don’t run thousand of apps… they run a few dozen or less. As long as Microsoft can encourage developers to write new apps that support computers with low power ARM processors and offer a high quality experience, users may not really miss the old apps they leave behind.

Every now and again it’s a good idea to drop backward compatibility. Windows Mobile 6.5 apps would look awful on a Windows Phone 7 device, and would you really want to run PalmOS apps on a webOS device? Then again, webOS may be a dying platform, and Windows Phone hasn’t exactly conquered the marketplace yet. It should be interesting to see if Windows on ARM can make any serious headway without support for older Windows apps.

Windows on x86 hardware, on the other hand, can easily handle pretty much any app that runs on Windows 7 — since Windows 7 and earlier versions of Microsoft’s flagship operating system only support x86 chips.

It could be another year before Microsoft releases Windows 8 to the public. During that time, we could see the company develop some sort of virtualization software that allows you to emulate an x86 environment on an ARM-powered device. But it’s likely that this would have a negative impact on performance and power consumption, thus negating some of the benefits of an ARM-based system.

Support Liliputing

Liliputing's primary sources of revenue are advertising and affiliate links (if you click the "Shop" button at the top of the page and buy something on Amazon, for example, we'll get a small commission).

But there are several ways you can support the site directly even if you're using an ad blocker* and hate online shopping.

Contribute to our Patreon campaign


Contribute via PayPal

* If you are using an ad blocker like uBlock Origin and seeing a pop-up message at the bottom of the screen, we have a guide that may help you disable it.

Subscribe to Liliputing via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Join 9,452 other subscribers

9 replies on “Windows 8 on ARM won’t run many older Windows apps”

  1. I working on writing a virus to run on Winblows 8 so you will have to buy my virus-removel app from the Microsoft store.


  2. Brad this was a really great article, on a day of really great articles from you, in a week of really great articles from you.

    I don’t think Microsoft is breaking backward compatibility.  In fact, it seems to be doing the opposite: creating forward compatibility.

    Apple likes to jump to new hardware platforms by creating software that is only compatible with the new hardware platform.  It’s a business model that obliges users to abandon useful stuff and buy new stuff (no wonder Apple flocked to embedded ARM garbage for their consumer junk devices).  This is breaking backward compatibility, and it’s not what Microsoft is doing.  In fact, Microsoft is preserving backward compatibility with its existing target hardware platform and expanding support to a variety of ARM-based SoCs.

    So let’s be explicit: Windows has not been previously compatible with ANY of these NEW platforms (well, at least since they were dropped by Windows NT.  You did know Microsoft supported ARM way before any of your beloved crap phone operating systems did, didn’t you?).  Because they weren’t previously compatible, there is no such thing as backward compatibility.  Because there is no such thing as backward compatibility, it can’t be broken.  I guess you could even claim that it’s been preserved vacuously, since the level of support for old stuff remains unchanged.

    This clarification distracts us from the real point.  Microsoft is adding new supported hardware platforms.  This is creating opportunities not just for those hardware platforms but for the people who want to use them.  It’s creating more choice for consumers, and that’s awesome.  It seems odd to complain that people still won’t be able to have things that they previously could never have, especially in light of the fact that they can now at least get to join in the experience of new things moving forwards.

    1. “Because there is no such thing as backward compatibility, it can’t be broken.” People who replace their old Windows computer with a new ARM Windows computer and find that it won’t run their favorite old game that they have been playing for years might disagree with you.

      “It’s creating more choice for consumers, and that’s awesome.” More choice is not awesome by definition. The 72nd cookie cutter Windows Netbook that is put on the market is not awesome, it just adds to the chore of choosing a good one. For most people reading Liliputing this may be an enjoyable chore, but for most people buying a computer it is not enjoyable. One reason that the iPad is the best selling PC in the world is because it minimizes the amount of choices that confuse people.

    2. “You did know Microsoft supported ARM way before any of your beloved crap phone operating systems did, didn’t you?”

      Actually, no.  Windows CE has been available for the ARM for a while, but Windows NT was only made for the x86, MIPS, and Alpha; Windows XP and 2003 also supported the Itanium architecture. 

      I do not think Windows for ARM will last very long; the point of Windows for x86 is that it can Quickbooks or your favorite game from 1999.  Windows for ARM does not have this advantage.

  3. Excellent summary of the legacy situation with Windows 8. Perhaps VMWare or Parallels will come up with software to run legacy Windows apps on ARM if Microsoft chooses not to do so.

    I can’t help but compare this with Apple. They sell more iPads per quarter than all Macs combined, and have since the iPad was released. iPhone sales are much greater. For them the question is: How can we move this big group of iPhone/iPad users to our desktop/laptop OS? Microsoft is trying to do the opposite, and their desktop/laptop users have been around much longer than Apple’s iPhone/iPad users.

    1. MS did announce they will be integrating features like Hyper-V into Windows 8…  If that works on ARM then they’ll have build in features that could support VM solutions for running legacy programs.

      A desktop OS like Windows should also work better with VM solutions and services like those provided by companies like Citrix.

      Though there is still a question of whether ARM hardware can provide enough hardware performance to facilitate these solutions, and what effect on power efficiency using such methods will impose on these systems.

      Legacy x86 programs are after all not optimized to be very power efficient and running any sort of emulation also adds additional load to what is needed to run those program.

      1. “there is still a question of whether ARM hardware can provide enough hardware performance to facilitate these solutions”.  

        Probably not; I can tell you that Qemu emulating ARM on an Atom (which is akin to an ARM emulating an x86, but the other way around) is too slow to really be usable.  

        1. Well, here’s the thing…  ATOM chips, except for some Z-Series ATOMs, don’t support hardware acceleration for virtualization.  However, ARM chips (especially the next gen based on Cortex-A15) can support hardware acceleration, which means virtualization could run better on them than what you experienced with ATOM.

          Though that alone doesn’t ensure all programs will work or run as fast as they do on native x86 hardware, virtualization is after all not a perfect solution, but it could mean they can run well enough and should be able to run anything that can run on a present ATOM system. Along with the fact they’ll mostly be running Quad Core designs, which also helps with multi-tasking and running VM environments.

          Keep in mind as well that while present ARM offerings have yet to rival Intel ATOMs, the ones being based on Cortex A15 are also moving to 28nm manufacturing process. 

          Mind that Cedar Trail is still only 32nm for ATOM.  Though this will still take some time as even the Tegra 3 coming out is still 40nm for comparison.  But means they can make them run faster and still be energy efficient versus the chips they can offer right now, with some like Qualcomm already stating they will offer up to 2.5 GHz solutions.  Though that doesn’t mean they’ll be that much more powerful than ATOMs, but they’ll no longer be at the bottom of the low end offerings either.

          So when Windows 8 comes out near the end of 2012 means we may see much more competition between ARM and x86 hardware systems.

          Though of course no ARM offering will be able to offer as much performance as Intel’s higher end offerings but until well into 2013 ARM may still be a good choice despite the limitations.

          While ARM also faces the problem that their CPU’s are still 32bit, which may be a problem for Windows 8 features like Hyper-V, which normally requires a fully 64bit environment to run.

          But a year from now means a lot can change and while there is likely to be growing pains, we may see Windows 8 finally make ARM and x86 hardware a almost interchangeable option.

Comments are closed.