ARM Battery Life Advantage Myth Lives On

Is Microsoft perpetuating the myth that ARM architecture processors have an unparalleled battery life advantage over Intel processors?

That would seem to be the case Friday judging from aggregated news reports on Techmeme discussing the latest Windows 8 and RT blog from Steven Sinofsky. Many reported that only Windows RT running on ARM will be able to run for weeks on a single battery charge while connected to the network in a mode called connected standby. My BYTE article was one of the few accurate stories pointing out that the new long battery life capability is on both ARM and Intel devices. MSNBC even quoted me--but continued to report that only RT will have connected standby.

Sinofsky seemed to have started the ARM-only connected standby misconception back in a February blog post. To be clear, Sinofsky briefly mentioned in both of his posts that Intel SoC devices will support connected standby, too, but that point was easy to miss. All the details focused on Windows RT capability, which is what the press has largely picked up in the last six months.

Microsoft seems to have little desire to clarify this confusion. That's because the only perceived advantage of Windows RT on ARM over Windows 8 on Intel is the myth that only ARM devices are power efficient enough to run all day. Once you debunk this perceived battery life advantage of Windows RT, all you're left with are its serious limitations. Windows RT won't run the vast ecosystem of Windows applications or PC hardware peripherals. Even Microsoft Office 2013 for Windows RT won't have full compatibility with Office because it's missing features such as macro support. These are among the reasons why Windows RT products including Microsoft Surface tablets are doomed to fail.

ARM won't dominate mobile much longer

ARM proponents have long argued that Intel couldn't possibly build a power-efficient processor because of the extra silicon Intel has to commit to x86 legacy overhead. Industry expert David Kanter of RealWorldTech explained to me that this isn't much of an issue because the legacy silicon is a very small fraction of total system power draw and it's nullified with Intel's more advanced chip fabrication process. Yet the widespread notion of ARM superiority in mobile persists because Intel had never produced very low power processors used in smartphones in the past and only launched its first Medfield x86 SoC for smartphones earlier this year.

Even when BYTE reported in June that Windows 8 running Intel Clover Trail x86 SoC will have always-on and all-day battery life, I was often met with skepticism and criticism that I had fallen for marketing hype. Critics ignore the fact that Intel Medfield x86 SoC has already been independently benchmarked by Anandtech, and Clover Trail is essentially a dual-core version of the single-core Medfield processor with beefed up graphics with Windows DirectX capability. Intel's roadmaps have been accurate in the past and were trusted enough for Apple to switch its entire product line to Intel processors despite the lack of publicly available benchmarks. The evidence points to very competitive battery performance in Intel SoC products running Windows 8.

The only difference between ARM and Intel is that all ARM systems will support connected standby, but only the SoC versions of Intel hardware will support connected standby. Desktops, notebooks, netbooks, and ultrabooks using Intel Ivy Bridge or Intel Atom Cedar Trail or any older Intel chips will not support connected standby. However, Intel soon will vastly improve connected standby support; in 2013 it launches Haswell, its first SoC processor designed for mainstream high-performance desktops and notebooks. As for x86/x64 systems from AMD, there is no word when AMD will support connected standby.

How Windows Phone 8 and Windows RT could thrive

Although the Windows App store is small today, a successful Windows 8-on-Intel launch could mean a bright future for Microsoft's store. That translates to good news for Windows Phone 8 and Windows RT on ARM-based smartphones and tablets because those apps can easily be made to run on everything from Intel desktops and notebooks to smartphones or tablets running on ARM. If Microsoft's app store succeeds, Windows on ARM stands a much better chance. But this hinges on a successful Windows 8 on Intel launch and that's where Microsoft might be getting ahead of itself.

There are 20 companies building fully capable Windows 8-on-Intel SoC devices. There are only four companies building limited-capability Windows RT-on-ARM devices so far. Yet Microsoft is heaping praise on Windows RT. HP, Acer, and Toshiba recently dropped out of the Windows RT race and they weren't happy with Microsoft's surprise entrance into the hardware business.

It seems that in Microsoft's haste to push alternative CPU architectures and possibly go it alone in hardware development, it risks diverting attention from Windows 8 on Intel SoC, which is its best chance for success.

Microsoft CEO Steve Ballmer said that Microsoft didn't leave any stone unturned when it built Surface, but some stones might be better off left alone for now.