Battery Life

When you consider something like a tablet, battery life is a crucial part of the complete package. Tablets are not meant to be plugged in for really any of their normal usage. In the case of the Surface 3, it has a 28 Wh battery onboard to power it when not plugged into the wall. That is a fair bit less than the 42 Wh battery that is crammed into the Surface Pro 3, but with a less powerful CPU, and a slightly smaller display, it may be able to compete.

To test battery life, we have several tests and for a device like the Surface 3 we will compare it to a couple of device types. First up, we will compare it against other tablets on our Wi-Fi test, which consists of basic web browsing. Next we can compare to notebook computers with our light test (again, web browsing) to get a feel for how it performs against those devices.

Surface 3 features Connected Standby support, but after a few hours of being asleep it will switch to hibernation. This is the same as the Surface Pro 3, and it helps tremendously with standby times. Although we do not have a test for this, in my time with the device I found that standby times were excellent, which makes sense since the device is actually turning off after a few hours. This does make for a bit longer wakeup the next time you need it, but it is a better result than the device being out of battery.

To enable a level playing field for all of the devices, we set the display brightness to 200 nits for all battery life tests, and disable any adaptive brightness.

Tablet Battery Life

Web Browsing Battery Life (WiFi)

Compared to other tablets, the Surface 3 has pretty poor battery life. On our web browsing test, the Surface 3 came in at just under eight hours. The iPad Air 2 has a similar size battery, but manages almost two hours more battery life in this test. The CPU workload is fairly light in this test, but without a complete breakdown of all of the parts inside it would be difficult to pinpoint exactly what is the issue here.

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

Update: May 18, 2015

After some discussions with Intel, I discovered that the battery life while playing back video was lower than it should be. Further digging into this issue found that the script being used to log the battery life time affected the tablet video playback test dramatically and resulted in much worse battery life result than was warranted. I have re-run this test several times with no script and was able to achieve 10.5 hours at 200 nits which is a much more respectable result. Further testing determined that this only affected the video playback times, and the other results were unchanged whether the script was running or not.

When this review was first published, we had tested the battery life at 7.72 hours of video playback. Upon subsequent research, it was determined that part of our logging in our battery life test caused an issue for unexpected CPU usage outside of the video decoder, and as a result, we are realigning the result to 10.5 hours. The issue in our test, based on retests of other devices, is currently only limited to the Surface 3 and specifically only to the video playback test.

On the video playback, the Surface 3 stumbles even farther, although the overall battery life is almost identical to the web browsing test. On the video playback many tablets are able to offload the work to hardware. Once again, without being able to check each part of the tablet individually it is not very easy to determine what is causing this weak battery life result.

So compared to tablets, the Surface 3 is about mid-pack in the video playback tests, and below average for web browsing. I hoped for a better result.

Laptop Battery Life

We have a different set of tests for notebook computers, so I also ran the Surface 3 through our light workload which is a different browser test.

Battery Life 2013 - Light

Battery Life 2013 - Light Normalized

The Surface 3 manages to outperform the Surface Pro 3 here, and at 8.5 hours on our light test, it is a decent result.

Battery Life 2013 - Heavy

Battery Life 2013 - Heavy Normalized

The situation is very similar under our heavy test. The Surface 3 once again outperforms the Surface Pro 3 here, however now it's by quite a bit more than it did under the Light test. Meanwhile compared to the Core M devices, only the Venue 11 remains well in the lead; the UX305's lead is down to 15%. Ultimately with a 2W SDP, the bulk of the Surface 3's power consumption is in the display, so ramping up for our heavy test does not have the same impact on overall power consumption as it does on devices with more powerful SoCs/CPUs. Meanwhile the situation also sees the Surface 3 do well on a normalized basis, well ahead of any other device with respect to the number of minutes of runtime per watt-hour of battery capacity.

Charge Time

The other aspect of mobility is charge time. Although longer battery life would always be a priority, the ability to quickly top up a device can make it a lot more useful in the real world where you are not always away from an outlet.

Charging time is always going to be a function of the battery size and the supplied charger’s ability to fill that battery. In the case of the Surface 3, Microsoft has shipped it with just a 13 watt charger, and when it is charging, only about half of that is available to the battery with the rest designated to power the system.

Charge Time

Battery Charge Time

Compared to notebook computers, the charging time is quite a bit longer than we are used to seeing. The Surface Pro 3’s proprietary charging connector was able to charge quite quickly, but the Surface 3 is really quite slow. Part of this comes down to the micro USB connector which is now the charging connector.

This connector is just not built for the high amperage needed to quickly charge a device up. Although I am happy to see Microsoft ditch the previous charging connector, this is where a USB Type-C connector would be much better. It can handle a lot more power, and it would have allowed the Surface 3 to come with a much higher wattage adapter. It really feels a bit like putting one foot in the past with the micro USB port. The long charge times were quite an issue for me trying to review this device, since we run our battery life tests multiple times to ensure a reliable result, but there was a very long wait to get the device ready for another run.

Display Wireless, Speakers, and Camera


View All Comments

  • TremecsSTi - Friday, May 29, 2015 - link

    I just found there is a very large elephant in the room that in 259 comments nobody has brought up.
    I had read this review and was still on the fence about what to buy but was leaning toward the iPad Air 2.
    I went in to the store determined to walk out with an iPad Air 2 if nothing else so I could learn the ecosystem (This is my 3rd attempt to do so but I always balk at the cost of Apple products).
    After picking up both tablets and comparing them the weight difference did not bother me as much as I thought it would. The 128/4 gb Surface 3 was $599, the 64/2 gb iPad Air 2 was $589.
    Looking at the lack of ports on the iPad I started looking at accessories to be able to connect it to everything, $30 to hook it up to my monitor, $20 to hook up my camera, $30 to hook it up to my TV, $89 for a keyboard, $69, for a mouse! $829 for the iPad Air 2 and I did not even get to the covers. So I am typing this from my $718 Surface 3 ($599 + the $119 type cover) with double the ram and double the storage, micro USB, Micro SD, USB, Micro HDMI built in.
    Looks like Apple lost out again but I just cannot justify the cost versus what you get. The quality of Apple products is hard to beat but the Surface 3 is very close and with twice the storage and ram for less money I could not pass it up.
  • blackcrayon - Saturday, May 30, 2015 - link

    The Surface 3 looks like it's only about half as powerful as the GPU in the iPad, I guess if you aren't doing anything graphically intensive (games) it won't matter... Otherwise I cringe at the idea of trying a 3D game that's expecting what's normally available on Windows (i.e. Windows games aren't going to be optimized to run on such a slow GPU). Reply
  • khanikun - Wednesday, June 24, 2015 - link

    You do know that Windows does everything a tablet does and did it before tablets were on the market? Also anyone who's invested money into any platform will have a hard time moving off that platform to another completely different platform.

    As for mixed bag, it's an all-in-one type device. Every single all-in-one type device has compromises. I don't have the Surface 3, but I do have the Surface Pro 3. Works great as both a tablet and as a notebook, so long as you don't actually want to use it in your lap. That's the only real downside that I find.

    Now, for the Surface 3, I find it being more of a resurgence of netbooks, except in an all-in-one tablet like device. A device that can do it all, albeit not great, but well enough. Not to mention it does it not quickly, as it uses cheap internals, to keep costs down. The problem with this is the fact that MS gave it cheap internals, but decided to build a quality chassis with quality accessories. So the price point was brought down, but not down enough to satisfy everyone's wants. Sure, MS could have built this thing in a cheap plastic chassis and provided no keyboard or stylus option at all and left consumers to fend for themselves and this would have brought the price down below that of less functional iOS/Android tablets, but this would have also infuriated many consumers.

    Really though, I find that MS did this right, minus the keyboard. The price point isn't unreasonable, when compared to less functional iOS/Android tablets. It's size and weight is well below that of convertible laptops. I just dislike the keyboard. Not it's feel or function, just that when you set it up in it's elevated position, it makes using the taskbar via touch, downright useless. I find myself having to remove it from the elevated position to access the taskbar via touch or use the crappy touchpad.
  • Ferrr - Wednesday, December 2, 2015 - link

    I have a Surface 3 LTE, purchased in October 2015 with all updates duly installed. On the screen appear random clicks, like if I was touching it (but I don't) at full speed, making appear menus, opening files, starting apps etc. making the device unusable.

    I had reset the device to no avail.

    Additionally, I experienced other problems:

    - "Autorotate on" appears on the screen when working with the keyboard attached (so, not rotating at all) stopping the device for some seconds.
    - A full charge needs 5-6h, with the device plugged in and switched off. If you want to work while charging the device, you will have a hard time: it charges extremely slowly (12h minimum needed) and in most of cases, if you have 2 or 3 "normal" (not very high energy consuming) apps open at the same time (outlook, word, edge), the device will keep on discharging, even plugged in.
    - The device loses battery when on sleep mode at a very alarming pace (around 5% per hour)

    I purchased the device in the US and I work in Russia. Now, with a worldwide guaranty, and in spite of having a filial in Russia, Microsoft asks me to ship the device, to pay for the shipping, to be delivered the new one in the US, and to pay the shipping again to my home in Russia...

    And the screen problem is known since 3 years, with thousands of people complaining on forums.

    Shame to Microsoft to keep on selling these crappy devices.

    If you don't know how to make computers and how to deal with customers, please stay away and let others like Apple do that.

    I deeply regret the day when I entered the Microsoft store to buy this.

    Someone else is experience the same ordeal?
  • q8wii - Friday, February 19, 2016 - link

    Thank you Reply

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