Battery Life: Good (60Hz) to Average (120Hz)

Last week we had published our initial battery life report on the S20 series, with some interesting findings. First of all, what needs to be mentioned again is that the new 120Hz display modes on the phones come with a quite large battery life impact. The behavior is exhibited on all our S20 models at hand and I think it’s likely due to the panel itself or the DDIC. Samsung had included various display refresh modes varying from 48, 60, 96 and 120Hz, however we have yet to find evidence of any mechanism that actively switches between the various modes. 

Device-On Black Screen Power Consumption (Airplane Mode)

As such, even on a black static screen, running at 120Hz comes with a quite steep power penalty that’s always present whenever the display is on, costing around 160mW of power.

I had noted that I found our variant of the Snapdragon 865 Galaxy S20 Ultra to have worse idle power than our Exynos phone version. Initially I had attributed this to possibly the SoC or even the nature of the external X55 modem, but since then I’ve also received an LG V60 and that device’s idle power is perfectly normal. The only other thing that differentiates our S20 Ultra here is the fact that it has the extra mmWave antennas and RF systems. It would be interesting to see if non-mmWave variants of the Snapdragon S20 Ultra behave any differently (Tip at our Chinese or Korean readers).

I also had made mention that the “Performance” mode of the Exynos S20 phones seemingly behaved quite overzealously in terms of its scheduling settings, and there was a quite drastic increase in power draw for what was not nearly an as drastic increase in performance. I’ve rerun the battery tests in the “Optimized” settings which doesn’t have the “Increased system speed” option enabled, and I’ve confirmed my suspicion as the battery life figures did improve by some notable amounts. I’ve also tested the Snapdragon in the “Optimized” setting and the runtimes only differed by 2% - for users having the Snapdragon versions it’s thus safe to simply leave that enabled.

Web Browsing Battery Life 2016 (WiFi)

In our web test, the new S20 series end up right about where you’d expect them to. The Snapdragon 865 Galaxy S20 Ultra at 60Hz fares the best amongst the tested models, and now represents Samsung’s longest lasting flagship device. Slightly behind it we find the Exynos S20 Ultra at 60Hz. The difference between the two phones here isn’t very big in this test, and I attribute this to the higher constant idle power draw of the Snapdragon phone which counteracts the much higher compute efficiency of the SoC. The Eyxnos S20+ ends up slightly behind the S10+ phones, but still lasts a good 12.65h in this test.

Once we turn on the 120Hz display modes, the battery life results on all the phones drops quite notably. The Snapdragon S20 Ultra goes from 14h to 11.3h, a 20% drop. The same applies to the Exynos S20 Ultra, with a 20% drop, but for some reason the S20+ sees a larger drop of 25%. In the systems performance section I did mention that there’s some software configuration differences between the Exynos S20 Ultra and S20+, maybe some of that plays part here in the results.

PCMark Work 2.0 - Battery Life

Overall, the conclusion on battery life isn’t quite as black & white as we thought it would be. The key point is to stay away from the seemingly broken Performance mode on the Exynos chipset and you’ll have roughly similar battery life results between the two SoC variants of the S20. Naturally, that’s only being achieved by the fact that the Exynos does showcase worse performance, saving energy by using the more efficient lower performance states more.

What’s valid for all variants of the phones is that the 120Hz display mode is quite the power hog. Samsung probably has the opportunity to improve this by introducing a better managed variable refresh rate mode that actually changes between the different refresh rates based on content, something that seemingly isn’t happening right now. Also switching to lower refresh rates when showcasing static content would be a huge power saver, but I’m not sure if Samsung would be able to actually deploy such a mechanism.

Display Measurement Camera Architecture: Huge New Sensors
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  • StrangerGuy - Wednesday, April 8, 2020 - link

    $1400? Geez, I thought $1100 for the Ultra here in Singapore was already stupid overpriced especially when all S20 variants here are only available in 128GB and the Note 10+ 256GB is just $590. Reply
  • Cliff34 - Friday, April 3, 2020 - link

    When I upgraded from s3 to s7, I was so impress by the new phone. Long battery life, great camera and fast cpu.

    Now I upgraded to s20+ and instead of feeling the aww feeling, I'm more like meh.

    It comes w great features but they are all come w a cost. Great camera but if you take 64meg photos, it takes a few seconds to process. Great screen but if you switch on 120 hertz, your battery drains fast.

    Hindsight, s20 is good enough for me.
    Reply
  • philehidiot - Friday, April 3, 2020 - link

    This is why I simply won't buy a new phone until I've waited for the Anandtech review. It takes a long time to come out and even longer to read but it has saved me a few bad decisions and premature upgrades. As well as a tonne of cash. I'm still on my S8 and the missus is on the S7 and y'know what? They're just fine. My only issue with the S8 is a recent update which is resulting in markedly increased screen brightness when set to auto. Try and drag the brightness back down and it just goes back up again. I can only imagine that "feature" was added to convince people it's time to upgrade. The only other issue is a bit of lag here and there but it's not a massive issue. I'm in the UK, so I absolutely will NOT pay Samsung for a product that is so inferior to other markets but they market and expect me to value exactly the same. I'm no problem with different internals for different markets and I've no problem with parts being sourced from different suppliers. BUT, you either change the price to reflect the value or you keep the specs of the different parts near enough the same if you want the value to be the same.

    Now, if you'll excuse me, for some strange reason my middle finger has gone stone cold and needs a rest. As if the blood has drained from it as a result of spending so much time erected in Samsung's direction.
    Reply
  • phoenix_rizzen - Friday, April 3, 2020 - link

    Install Lux and let that manage the auto-brightness. On the S6, S7, and A8 (2018), Lux does a much better job managing brightness than Samsung's settings. And you can set your own targets for "at this level of ambient light, set the brightness to this level", which is especially handy for lower light levels.

    On the S10e, I haven't bothered to install Lux, as Samsung's Adaptive Brightness eventually catches up to my preferences and is working well enough.
    Reply
  • philehidiot - Friday, April 3, 2020 - link

    Ahh sweet, cheers! I'll have a look at that now. The adaptive brightness has worked fine for several years and only since an update has it gone very strange. Reply
  • shabby - Friday, April 3, 2020 - link

    Can all the cameras on the s20+ record in 4k60fps? In the s10 only the main one could so you couldn't record in 4k60 while switching between the sensors. Reply
  • Andrei Frumusanu - Friday, April 3, 2020 - link

    It's unfortunately still only limited to the main camera module. Reply
  • shabby - Friday, April 3, 2020 - link

    Damnit Reply
  • iamlilysdad - Friday, April 3, 2020 - link

    While waiting for display accuracy comparison charts, can you post "old style" dE results so we can do our own comparisons? Or, even better, provide a timeline and list of devices that you're going to go back and retest using the new methodology/rating system? Reply
  • FunBunny2 - Friday, April 3, 2020 - link

    I'm not a phone junkie, doh!, but isn't refresh rate tied to content/application coding? IOW, only content/applications written to display at 120 will benefit? Otherwise, won't the screen just refresh twice on the 60hz line? Reply

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