Battery Life and Thermals

With the performance aspects out of the way, let's turn to battery life. I have to say, I've run more battery tests on the Acer S7 than perhaps on any other laptop in recent history. It's not that it needed extra testing, but as the first Windows 8 laptop in our labs I wanted to look at changing some of the tests. We discussed things among the various editors, and I worked to come up with some redesigned, hopefully better battery life tests.

First on the chopping block is the idle battery life test; rarely do people use workloads that are so light that it's meaningful to look at pure idle battery life, and going to the extreme of muting the volume and turning off WiFi is more than most are willing to do. We've decided to move to our Internet test as the baseline measurement, since it's representative of a moderate workload that conceivably might be used while running a laptop on battery power. With moderate Internet surfing (we load four pages every minute, simulating time for reading) as our light workload, for our heavy workload we crank up the frequency of page loads (the same pages, only loading every 10 seconds now) and add in playback of a bunch of 128kbps MP3 audio files. Finally, for our heavy workload we keep the Internet portion of the moderate testing but add in looped playback of a 1080p H.264 encoded video and have a constant 1Mbps download running from a local server.

With this being the first laptop to use our new Windows 8 test suite, we're in a bit of a state of flux so I've run both the new battery tests along with the old Windows 7 era tests (only with IE10 instead of IE8/9). I also ran a few other battery life tests just for reference: the three PowerMark tests. We're a little hesitant to use PowerMark as a standard, simply because it's limited to Windows platforms and has the potential to encourage optimizations for a benchmark as opposed to general optimizations; as you'll see, however, there's plenty of overlap between our tests and the results from PowerMark.

Battery Life - Idle

Battery Life - Internet

Battery Life - H.264 Playback

Battery Life Normalized - Idle

Battery Life Normalized - Internet

Battery Life Normalized - H.264

Starting with our older 2012 battery benchmarks, the Aspire S7 has a pretty poor showing. The 35Wh battery is the same capacity as the previous generation Aspire S5, and yet battery life is down substantially in all three tests. Whatever Acer (or Microsoft) has done in the past six months has not been helpful in this area. Normalizing for battery capacity does improve the situation a bit, but where it’s enough to move Acer past the two Toshiba Ultrabooks and the HP Envy 14, that’s not saying a lot—and higher battery capacities do count for something. The bottom line is that best-case, we were able to get just over five hours of running time out of the Aspire S7. Let’s look at some other results.

Acer Aspire S7 Additional Battery Tests
Battery Test Run Time
(Minutes)
Normalized
(Min/Wh)
AnandTech 2013 Light 240 6.86
AnandTech 2013 Medium 173 4.94
AnandTech 2013 Heavy 137 3.91
PowerMark Productivity 255 7.29
PowerMark Balanced 201 5.75
PowerMark Multimedia 172 4.91

Note that in the above tests, we’re using 200 nits for our 2013 test suite while PowerMark specifies 110 nits as their desired brightness level. Our Light test result is down 21 minutes from our previous Internet test result, most likely due to the increased LCD brightness. Elsewhere, our new Medium test drops us below the three hour mark, and our Heavy test is getting close to lasting only two hours. It’s not really realistic to expect a full day of use from a laptop when you’re going full-tilt the whole time, but considering the CPU load is only around 10-35% even in our Heavy test, we’re not pushing things that hard.

Windows 8 Tablet Performance Display Quality
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  • rarson - Thursday, January 10, 2013 - link

    First of all, it depends on the type of accident. I can guarantee you that a head-on collision with a wall at, say, 30 mph will be safer in a Smart Car than an Oldsmobrick.

    The fact of the matter is that when it comes to protecting the passenger, crumple zones and safety cages are more important than mass. Today's cars are designed to absorb the energy of the crash, to soften the impact on the passenger. Older cars were designed with the mentality that if the car survived mostly unscathed, then the passenger would as well, which is obviously incorrect. If safety is your primary concern, then you're better off looking at crash testing than vehicle size or weight. But the absolute best way to increase your safety is to become a better driver.
    Reply
  • Tech-Curious - Thursday, January 10, 2013 - link

    I can guarantee you that a head-on collision with a wall at, say, 30 mph will be safer in a Smart Car than an Oldsmobrick.

    The fact of the matter is that when it comes to protecting the passenger, crumple zones and safety cages are more important than mass.


    It's a matter of mass and size. Your guarantee is preposterous, because a Smart Car has precious little space within which to crumple, without also crumpling the people inside of it. The size of the wheelbase, the cabin, and yes, the mass of the vehicle are all important.

    I've been in a head-on collision in a compact car with a much heavier object (a semi-truck). Trust me when I say that I'm lucky to be alive; if I hadn't swerved at the last second, I would have been vaporized, because the truck literally drove through the right side of my engine compartment, and didn't come to rest until its front bumper was sitting on my passenger seat.

    Thank god no one was sitting there. The truck's damage? A cracked headlight.

    Now, if I had been involved in the same accident in an Oldsmobrick, as you call it, the car would much more likely have kept something approaching its original shape. A passenger or I could have died from the internal trauma caused by the savage stop; that's true -- but the passenger would have died in more-or-less one piece.

    Let's not kid ourselves: The Smart Car is little more than a roofed motorcycle, for all the protection it offers your body. Many modern cars are safer than their (often heavier) ancestors, but I chose the Smart Car because it represents an extreme, and I thought (erroneously, as it happens) that the extreme example would illustrate the point without courting controversy.

    And yes, good driving habits comprise the best safety measure available -- but it's a mistake to assume that you're ever 100% in control of any situation on the road. The essence of safe driving is to understand that you don't have that control, to minimize your risk by putting yourself into the best position to react to sudden hazards. Even so, not all hazards are avoidable.
    Reply
  • Tech-Curious - Thursday, January 10, 2013 - link

    Oh, and with regard to crash testing, you have to be very careful. Tested safety ratings might rule out weight and size: for instance, the Smart Car recently got a safety rating similar to the Trailblazer's -- but you'd have to be out of your mind to conclude that both vehicles are equally safe.

    The Trailblazer is simply at the same level, relative to its analogues, as a Smart Car. A couple of statements from (or paraphrases of) the president of the Insurance Institute from Highway Safety follow:

    “All things being equal in safety, bigger and heavier is always better. But among the smallest cars, the engineers of the Smart did their homework and designed a high level of safety into a very small package,” Lund said.

    (From http://www.msnbc.msn.com/id/24599768/ns/business-a...

    In new crash tests, the Insurance Institute for Highway Safety rammed three automakers' smallest cars into their midsize models. Although the small cars had passed other IIHS tests, they flunked in collisions with larger but still-fuel-efficient sedans. "The safety trade-offs are clear," IIHS President Adrian Lund says. "There are healthier ways to save gas."
    (from http://usatoday30.usatoday.com/money/autos/2009-04...

    "We're hearing people say, 'Everything gets a 'good' rating now, so I might as well buy a small car,' " Lund says. "A lot of people are forgetting that the laws of physics still hold" and even a little bit bigger still is safer.
    (from http://usatoday30.usatoday.com/money/autos/2009-04...

    And finally, the tale in pictures. Trailblazer: http://media.caranddriver.com/images/media/191279/...

    Smart Car: http://node1.ecogeek-cdn.net/ecogeek/images/storie...
    Reply
  • rarson - Thursday, January 10, 2013 - link

    "Once you get to the point where the price isn't as much of an issue (especially for something you'll be using for 4-5 years) the enjoyment of using something that has high-quality interface points (monitor, keyboard, etc.) quickly overcomes the cost difference."

    In that case, the Acer (and the Macbook Air) fail completely. I've got a $350 Trinity laptop that I'm using right now that has a much better keyboard than both of these, and even my old PII Compaq laptop is DRASTICALLY better. I understand what you're saying about touchpads (the laptop I'm using definitely has some quirks that can make the touchpad frustrating), but I find it laughable when people call these devices "high quality" when they have such terrible keyboards.
    Reply
  • rarson - Thursday, January 10, 2013 - link

    1) Uh, every device that I've tried feels fragile in my hands due to the actual thickness, not the construction or materials. That's why I said I "feel" like I'm going to break the thing.

    2) Well that's just absurd. Anyone can easily see the value of a Mercedes. You can't tell the difference between a car with solid body construction and quality sound deadening? It's a pretty marked difference between, say, a typical economy car. You don't seem to understand the difference between seeing the value and actually desiring it.

    There's no exceptional build quality here. The device isn't going to last longer or significantly outperform a comparably equipped, but much cheaper laptop. All you're getting is a decent display (with the added cost of touch), a slimmer chassis, and an unjustifiably higher price. So where exactly is the value proposition here?
    Reply
  • The0ne - Monday, January 07, 2013 - link

    This is an Ultrabook laptop. These are usually not cheap to begin with because they are Ultrabooks. Why are people comparing these to notebooks that are not even in the same class? These are not even in the same class as business notebooks as well. Subjectively, these are expensive because they are light and thin. Most of the readers here won't even consider buying one to be honest or may have never own an ultrabook before. The market for these are business travelers where they need the light weight and thinness to carry it around for long periods of time.

    I just don't understand why people would complain about something that they don't begin to comprehend what it is and what market it is aimed at.
    Reply
  • rarson - Thursday, January 10, 2013 - link

    You're right, I don't comprehend what market these are aimed at, since a regular laptop is only about a pound heavier than this thing, and might actually offer a decent keyboard and slightly larger screen real estate, things that I'm pretty sure would be far more important to the average businessman than "thin and light," at a significantly lower price, no less.

    Perhaps you could explain to me why a businessman would need a touchscreen on a laptop, or 1080p resolution in a 13" screen.

    You said it above: "These are usually not cheap to begin with because they are Ultrabooks." Right, they are'nt cheap because they're marketed as expensive devices. I'm sure it costs more money to make the thinner, lighter chassis. But that doesn't mean that it makes sense to pay more for it.
    Reply
  • jabber - Monday, January 07, 2013 - link

    .....did we get a indication of what this machine is like out of the box?

    In other words -

    1. How long did it take from first switch on till actually being able to use it properly?

    2. How much crapware was installed and how long did it take to uninstall?

    I have known Acer laptops (and others from similar companies) to take a couple of hours messing around till you can actually use them. I love the ones that force you to burn a set of recovery disks at start up and threaten thats its a once in a lifetime deal.
    Reply
  • bobjones32 - Thursday, January 10, 2013 - link

    I posted elsewhere in this thread with my impressions, but my wife purchased this from a Microsoft Store. That means it comes with a Signature image, so no bloatware, and ready to use straight out of the box.

    The thing turned on instantly, set up quickly, and she was using it fully within just a few minutes.
    Reply
  • thesavvymage - Tuesday, January 08, 2013 - link

    I seriously do not understand on having the "thinnest" laptop you can have. You dont hold it in your hands, it sits on your lap. The screen size and overall volume are what matters the most (for bulk). This laptop is .5" thick. If they even increased it to .7", they couldve added a bigger batter and better cooling, and it wouldnt even seem that different to anyone without a milimeter caliper. Reply

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