So, the Surface has been out for about 7 weeks as I write this and I finally managed to get all of my data together to do some real-life Surface Pro 4 battery life benchmarks. Part of this delay was to give Microsoft a chance to address some ongoing battery issues with the November Update which was released in mid-November.
I’ve done this type of testing for previous Surface models and many people have found it much more useful and accurate than synthetic benchmarks created by battery testing software (which many reviewers use).
So, let’s get to the test results…
Surface Pro 4 Battery Life: Benchmarks
Here are the results for all three SP4 CPU models (m3, i5, i7). For these tests, in the interest of scientific rigor, my testing procedure was as follows (unless noted otherwise in a specific section):
- The m3 SP4 had 4GB or RAM and a 128GB SSD
- The i5 and i7 SP4s and 8GB of RAM and 256GB SSDs.
- The Surfaces were all patched up as of November 15th (and included the November Update).
- The Surfaces were not updated during the test sequence (to keep the patch level consistent throughout the tests).
- The tests were run 6 times for each model and averaged to get the results below.
- The devices were fully recharged and restarted before each test run.
- The default “Balanced” power plan was used on each device.
- Screen brightness was set to “Suggested”.
- The devices were used until the critical battery action put them into hibernate at 3% remaining capacity. All low power messages were ignored.
- None of the three devices I tested seemed to suffer from any issues or bugs that caused premature battery drain.
- If I got an “outlier” result (such as the battery only running half as long during a single test), it was discarded and a new run was performed.
- Results were rounded to the nearest minute.
Now that you know what my testing procedure was like, let’s move onto the actual benchmarks…
Surface Pro 4 Battery Life: Normal Use
In this scenario, I tested a “normal use” scenario. Basically, I used the Surfaces to do things like web surfing, blogging, editing pictures, light graphics work, email, Facebook, streaming videos, etc. In other words, I basically just used them to work and web surf like any normal day.
I let the SP4s turn off the screen and sleep normally when I wasn’t using them, but I did not power them off or press the power button to sleep them manually.
This graph shows minutes of battery life during normal use, including when sleeping:
All three tablets would have made it through a normal 8-hour work day but, the m3 model would have just barely squeaked by at 7 hours and 54 minutes. By comparison, the i5 model gave me, on average, 10 hours and 4 minutes of life
This graph shows the total battery life while the Surfaces were actually powered on and in use (not including sleep):
You might be surprised how poorly the m3 version did with this test. At 376 minutes (6 hours, 16 minutes) of average total run time, it had a battery life that was even less than the average for the i7 version. However, nothing was wrong with the test. It seems that the m3 version of the SP4 is simply less efficient than the other models.
If you try these tests yourself, the results will vary depending on the types of software you run, power settings, and how often you let your Surface go to sleep. I tend to let my let my Surfaces sleep about 30% of the time during the day and I don’t tend to run high-intensity apps like Mathematica, Lightroom, or Lumion. Inversely, I do often run several web browser windows at once and I often have MS Paint and/or Excel running in the background; so, I am taxing the CPU a little bit, just not a lot.
Surface Pro 4 Battery Life: Streaming
For this test, I fired up the Netflix app and simply played back to back videos until the battery was exhausted. There were minimal gaps between videos (sometimes I had to deal with the “are you still watching” prompts). this test does a good job of simulating being on a long flight and passing the time by streaming movies. I did the same thing with YouTube (in Chrome).
The results are as follows:
Correction: The original graph for this section was incorrect. The m3 data was good but, the data for the i5 and i7 models were from a different test that I decided not to use (powered on, doing nothing). The graph above is the corrected version. The other graphs were double-checked and are correct.
As you can see, the m3 model once again is lagging behind the i5 model but, has a slight edge on the i7 model. Streaming from the net uses Wi-Fi quite a bit but it shouldn’t be a huge tax on the CPU; so the m3, in theory, should have an advantage.
It also seems that the Netflix app is a little more efficient than YouTube on Chrome, which is not really a surprise.
Surface Pro 4 Battery Life: Gaming
For this test, I fired up SP4 is lacking) but they are still pretty good and it draws each spacecraft component separately which adds to the CPU load.
Here are my results:
The m3 finally outperformed the i5 and i7 for battery duration. However, even though the battery lasted longer, it was much more painful to play KSP on the m3 than the others.
Often, I would have framerates in the single digits when I had more than one small spacecraft on screen. The i5 was quite playable most of the time (but would lag if I had a lot of objects on screen) and the i7 version played pretty smoothly no matter what I had on screen (up to the point I put a monster space station with 628 individual parts in orbit, anyway).
Funny enough, if you look at my post on the Surface Pro 4 for this test but that’s probably because the SP3 has a battery with a larger capacity.
Surface Pro 4 BatteryLife: Recharging
While depleting the battery is usually more fun, how quickly you can recharge your SP4 is pretty important, as well. So, here are the results of my testing where I recharged the SP4 models from 3% back up to 100%. The tablets were not in use during the charge cycles:
This time, the result is pretty much a draw as all three versions recharge in a little over 2 hours and 30 minutes. Since the m3 version of the SP4 comes with a 24W charger (as opposed to the 36W version that comes with the i5 and i7 versions), I was a bit surprised by this result.
Surface Pro 4 Battery Life: Conclusion
So, according to the marketing folks, the low-end m3 version of the SP4 should have the best battery life. Unfortunately, it clearly doesn’t. I poked around online looking for other SP4 m3 battery reviews and it seems that SP4 that was pretty similar to mine. This makes me think that my testing wasn’t flawed and that there’s something wrong with the m3 equipped SP4 when it comes to power management.
Overall, the i5 version seems to do the best job of managing battery life and, as a bonus, it has more computing power than the m3 model. So, if you want the best battery life from your Surface Pro 4, opt for one of the i5 models.