Battery Life

Performance isn’t the only benefit that comes with Tegra 4 – NVIDIA and Microsoft also enjoy a smaller/lower power process: TSMC’s 28nm HPL. Of course four high-clocked Cortex A15 cores drives max power consumption higher than on Tegra 3, but idle power consumption and power efficiency at lower clock speeds should be better. As with most present day mobile devices, the move from Surface to Surface 2 comes with an increase in dynamic range of power consumption. I put Surface 2 (as well as Surface RT) through our 2013 tablet/smartphone web browsing battery life test and came away with around 8 hours of use on a single charge. That’s definitely not the lowest power that we’ve seen, but it is an improvement over the 6.8 hours Surface RT managed in the same test.

Web Browsing Battery Life (WiFi)

As with all modern Tegra SoCs there’s one extra “companion” core designed to be used for lower power/performance operation. Unlike under Android, there’s no hot plugging of CPU cores under Windows RT – there are always four Cortex A15s presented to the OS/scheduler, regardless of whether or not the companion core is active. Microsoft tells me the companion core is used on Surface 2 (unlike its predecessor), however specifics are tough to come by. Microsoft claims the companion core is used during full screen video playback. The only thing I can think of is that the hardware migrates the companion core in under certain circumstances, taking the place of one of the four A15s, and software specifically sets processor affinity in this case. I tried confirming whether or not this was the case by playing a movie and inspecting the process under task manager, unfortunately I came up empty handed. The video playback process wasn’t set to run on any one core in particular, it was allowed to run on all four exposed cores.

Video Playback Battery Life (720p, 4Mbps HP H.264)

However it’s used, the impact seems to work relatively well. Surface 2 managed just over 10 hours of battery life in our video playback test. It’s not the best we’ve seen in this test, but it’s definitely competitive with other flagship devices.


Surface 2 ships with Windows RT 8.1, and similarly absorbs all of the improvements that 8.1 brought to x86 machines as well. A number of ARM specific optimizations are under the hood, which should help improve both performance and power consumption.

The biggest issue with Surface 2 remains on the software front. Developer support for Windows Store applications is no where near where I thought it would be by now. There are some big ones (Netflix, Facebook), but there’s still no good Twitter client, no amazing IM client, and of course you don’t get good integration of Google services anywhere (outside of leveraging Mail for Gmail access).

Without opening up classic desktop APIs to developers, we won’t see alternative web browsers like Chrome or Firefox on Windows RT 8.1 either. Although IE11 does a relatively good job on the touch front, I find that heavy multitasking with IE11 on Surface 2 can result in a lot of hangs and crashes within tabs or the application itself. I can understand Microsoft’s hesitation on this front (better control over the platform if you don’t open it up), but I can’t see a future where Windows RT is successful and Microsoft doesn’t allow developers to access both sides of the platform.

SoC, CPU & Performance Final Words


View All Comments

  • Serr - Wednesday, October 23, 2013 - link

    "Although IE11 does a relatively good job on the touch front, I find that heavy multitasking with IE11 on Surface 2 can result in a lot of hangs and crashes within tabs or the application itself."
    There goes the truth! You don't have that even on iPad 2.
  • Wall-Swe - Saturday, October 26, 2013 - link

    @Serr Well that's a lie! My iPhone 4 is crashing almost everyday when using Safari.
    @Anandtech How come you only got 8hour of battery out of the Surface 2? Engadget got 14hours 22minuties, it its the best score they have had of any tablet!
  • MarcSP - Sunday, October 27, 2013 - link

    Yes, that discrepancy makes no sense. Or Anandtech’s device had some problem, or Engadget made a big mistake in the method they used. I know that of these options seems much more likely than the other ;-), but without more testing there is no way to know for sure. Reply
  • whatsa - Friday, November 1, 2013 - link

    Theres video and video

    I can tell you I dont get the numbers stated with a BD rip....

    if its close then thats good enough for me as I have yet to see a standard for this
    testing used across the board. (I may be wrong so if you need to shoot aim for the leg)
  • MarcSP - Sunday, October 27, 2013 - link

    It is specially weird that Surface 2 got less battery life for video than Surface 1, when MS said battry life shoudl be 25% better and that now, unlike before, they are using the companion core for that task. Reply
  • TechFan1 - Sunday, October 27, 2013 - link

    If this had bay trail inside I would already own one. Really disappointed they went with Tegra 4 :( Reply
  • melomania - Sunday, November 3, 2013 - link

    Why in the ipad air review, does this machine only score a 750 in contrast ratio and here it is over 1000? Reply
  • JBVertexx - Monday, November 11, 2013 - link

    I'm thinking of picking up one of these for my 7th grade son. He's had a Nexus 7 since that first came out. He uses that mostly for gaming. But this year, he needs a "device" for school. The Nexus 7 hasn't really been up for class note-taking, etc. Thinking this would be the perfect solution. Reply
  • Hoekie - Sunday, November 24, 2013 - link

    Great review, but fails on the search for apps.
    Like telling us that there no Twitter app, make me worry you did not get a good look at the Store and have setting set to 'easy to find local apps'
    The official Twitter app for instance in the Windows Store for quit a time now. Nice thing also is that it can be snapped to the left. A link in a tweet makes the browser open that link. All on the same screen. Killer!

Log in

Don't have an account? Sign up now