Is the performance of AMD Ryzen mobile on battery really that bad?
If you’re even asking that question, you’ve no doubt heard Intel’s claims that Ryzen 4000 CPU performance tanked when running on battery. Plugged-in performance was dandy, but in tests of multiple Ryzen 4000U-based laptops, performance dropped huge amounts on battery, depending on the task.
While some reviewers checked AC and DC performance and found some nuggets of truth to Intel’s claims, the issue has mostly lain dormant for the last six months. Now that Ryzen 5000 is out, we decided to circle back and see if the claims still held. As you’ll see in our tests, what’s “good” or “bad” depends on whether you care more about performance or battery life.
How we tested
For our testing we used the same two laptops from our Ryzen 7 5800U review:
- Asus ZenBook UM325. It features AMD’s eight-core Ryzen 7 5800U, 16GB of LPDDR4X/4267, a PCIe 3.0 1TB SSD, a 65-watt-hour battery, and a 13.3-inch 1080p OLED, and it weighs 2.6 pounds.
- MSI Prestige 14. It features Intel’s four-core 11th-gen Core i7-1185G7, 16GB of LPDDR4X/4267, a PCIe 4.0 512GB SSD, a 52-watt hour battery, and a 14-inch 1080p IPS-level screen, and it weighs 2.7 pounds.
It’s important to note that there’s almost no such thing as an apples-to-apples comparison with laptops. Intel and AMD give laptop makers the CPUs, but everything else is specific to the vendor’s design for that system, from the display type and size, to the cooling design and the keyboard and the battery. Think of laptops instead as pairings of a specific design to a specific CPU—in this case, Asus ZenBook with Ryzen, and MSI Prestige 14 with Core i7. These two laptops were among the first out of the gate with their respective CPUs, so they are representative of what to expect.
Both laptops were running Windows 10 20H2 (Build 1904.867) and the latest drivers available. Windows 10 offers four power performance states you can select when using. According to Microsoft documentation, they are:
Best Performance: Favors performance over power and is targeted at users who want to trade off power for performance and responsiveness. Available on both AC (plug-in electricity) and DC (battery).
Better Performance: Default slider mode that slightly favors performance over battery life and is appropriate for users who want to trade off power for better performance of their apps. Available on both AC and DC.
Better Battery: Delivers longer battery life than the default settings on previous versions of Windows. Available on both AC and DC. In some cases, users will see this mode labeled Recommended, rather than Better Battery, in their slider UI.
Battery Saver: Helps conserve power, and prolong battery life, when the system is not connected to a power source. When battery saver is on, some Windows features are disabled, throttled, or behave differently. Screen brightness is also reduced. Battery Saver is only available on DC.
For our testing, we used only the first three modes, because it’s understood that Battery Saver mode will involve a performance degradation. The ZenBook’s default unplugged mode is Better Battery, while the Prestige 14’s is Better Performance.
Cinebench AC/DC Testing
We’ll kick this off where we typically begin: Maxon’s Cinebench R20 3D rendering benchmark. It’s a test built on the company’s Cinema4D engine, which is integrated into Adobe’s Premiere and After Effects, and is also sold standalone. Like all 3D modelling applications, it favors more CPU cores and threads.
On this and all charts to follow, we show the AMD chip in red, and the Intel chip in blue.
In the first chart, for Cinebench multithreaded performance, the top pair of bars shows the stomping you’ve come to expect when pitting an eight-core CPU (AMD’s Ryzen) against a four-core CPU (Intel’s 11th-gen Core)—when running on AC, anyway. Once we switch to DC battery, for all other results shown below, you can see the drastic fall-off in performance for the Ryzen-based Asus. The four-core Intel chip gets uncomfortably close. However, you don’t see steeper declines as you move through the lower performance/power stages.
Using Cinebench R20 set to a single thread, we can see both laptop/CPU combos exhibit very different behaviors. The Core i7-1185G7 in the MSI basically doesn’t move going from AC to DC in Best Performance or Better Performance. Meanwhile, the Ryzen 7 5800U in the Ryzen is really chugging in the Better Battery setting in single-threaded tasks.
Let’s take those Cinebench results and look at how both laptops compare as a percentage. In multi-core mode, you can see the Ryzen’s advantage range from a whopping 50 percent to narrower leads running on DC battery in the other power settings.
In single-threaded performance we see an inverted chart. That’s because while the Prestige 14/Core i7 was actually competitive with the ZenBook/Ryzen 7 on AC, we’re looking at a 27-percent to 45-percent lead for Intel on the DC battery settings. That’s a major difference, and we’ll likely see this manifest itself later on.
Ryzen vs. Core i7: Photoshop and Lightroom AC/DC
We know very few people perform 3D modelling or rendering on a 13-inch ultraportable laptop, so we use Adobe Photoshop 22.3 and Lightroom Classic 10 with UL’s Procyon Photo test as something that’s popular but not exactly lightweight, and still CPU- and GPU-intensive. Procyon runs both Adobe apps through a set of scripted tasks while measuring the response.
The good news for Ryzen in the Asus ZenBook is it’s outpacing Intel’s best U-class CPU in the MSI laptop. The nagging problem, though, is once you’re on battery, even on the laptop’s “Best Performance” setting, the ZenBook and Ryzen 7 are giving up 24 percent in performance in Photoshop and Lightroom against the Intel/MSI pair.
Performance gets even harsher for the ZenBook/Ryzen 7 running on the Better Battery setting. It’s basically cut in half versus the MSI Prestige 14/Core i7.
With such a powerful suite as Photoshop, what you do can influence performance. We get a second opinion from workstation builder Puget Systems and its PugetBench 0.93 test.
We again see the Prestige 14 and Core i7 hold steady in performance between AC and DC using the “Best Performance” setting. The ZenBook and Ryzen 7 combo again sees a drop in performance from AC to DC.
As with Procyon, PugetBench for Photoshop again sees a pretty drastic performance drop on “Better Battery.”
Keep reading for performance in Office, Edge browser, and more
Ryzen vs. Core i7: Office AC/DC
Let’s be honest, most people wish they could be editing photos from a month-long trip to Bali on their 13-inch ultraportable, but they’re more likely massaging Word and Excel files, or making a PowerPoint presentation using pictures from their boss’s trip to Bali.
To look at Office performance under AC or DC conditions, we use UL’s PCMark 10 Application, which, like Procyon, uses the full version of Office 365 to test Word, Excel, PowerPoint, and Edge performance.
The big win for the ZenBook/Ryzen has been its performance under AC, where, despite the very lightweight nature of Office, it actually beats the Prestige 14/Core i7 pairing.
Unplug the ZenBook and Prestige 14, and we see the Intel Core i7 jump to the front. We’d argue you’d hardly feel it in most tasks, but it is a bit eyebrow-raising to see the performance of the Ryzen 7 in Excel sharply drop off by 30 percent. Again, we’re using the “Best Performance” setting.
Moving the Windows 10 slider to “Better Battery,” we now see both laptops’ results slack off quite a bit. The Prestige 14/Core i7 remains in front of the ZenBook/Ryzen 7, which again gives up almost half.
Ryzen 7 vs. Core i7: Browsing AC/DC
We’ll step back to an even lighter-duty task, but one that many people do on a tiny laptop unplugged: Browse the web. To gauge performance we ran both laptops through Principled Technologies’ WebXPRT 3, as well as JetStream 2, MotionMark 1.1, and Speedometer 2.0.
As we did above, the darker blue represents Intel on AC, while the darker red represents AMD on AC. The lighter colors represent DC performance with the Windows 10 slider set to “Best Performance.” We used the same version of the Google Chrome 90 for both laptops.
Again, the big win here for AMD is on AC in the ZenBook, where it’s now performing ahead of Intel’s best low-power CPU in WebXPRT 3. The other tests also show it to be mostly a back-and-forth—on AC.
Unplug those laptops, though, and we now have a solid lead across the board for the Intel/MSI pairing.
Set the laptop to its “Better Battery” test, and both laptops fall off in performance even more—but the Ryzen 7 in the ZenBook falls off furthest. WebXPRT 3, for example, shows about a 30-percent drop for the Core i7, while the Ryzen sees closer to a 50-percent performance drop.
What about power consumption?
It’s impossible to separate the laptop from the CPU when talking about battery life. What screen is used, how much memory, how good the motherboard’s power modules are, driver optimization, and battery capacity all contribute to the laptop’s endurance.
Our official test for battery rundown loops a 4K video, with the laptop set to airplane mode and its screen set to 250 nits to 260 nits’ brightness. We also set the volume to medium and plug in earbuds.
As you can see in the chart below, the OLED Asus ZenBook and its honking-big 65-watt-hour battery (dark red bar) does pretty well, exceeding 12 hours of run time. The MSI Prestige 14 also just breaks 12 hours with its smaller 47-watt-hour battery. However, this is a pretty easy test, and your mileage will vary depending on what you actually do.
So we took it a step further and looked at how much power is consumed in the laptops during many of the tests. Reported wattage doesn’t always translate to direct battery life, so instead we tracked the battery discharge rate of the laptops while running some of the tests again, unplugged. Every watt used denotes a drain on your battery.
Below you can see both laptops running Cinebench R20. The first run is using the “Better Battery” setting in Windows 10, while the second is using the “Best Performance” setting. The result is in milliwatts.
You can see part of the magic of the Core i7 in the MSI on battery is due simply to using more power—sometimes a lot more. In the first Cinebench R20 run, it’s almost a 40-watt load, spiking up to a massive 70 watts in “Best Performance” mode before completing the run mostly in the 55-watt to 50-watt range.
The Ryzen 7 in the ZenBook is far easier on the gas pedal, with the battery discharge rate at roughly 15 watts in “Best Battery” and about 20 watts in “Best Performance.”
As you can guess, putting that heavy of a load on a battery means you’ll run it down far faster. In our testing, the dent in the MSI Prestige 14’s battery was visibly different after the Cinebench runs, unlike with the Asus. To be fair, the Asus’s battery is 38 percent larger, so any reduction in capacity appears larger on the MSI. But more power used means less run time, no matter how you cut it.
An all-core load is still very unrepresentative of what most people do, so we also looked at the discharge rate of both laptops doing everyday practical browsing.
Below you can see WebXPRT 3 running on Google Chrome 90 in “Best Performance” mode, and then “Better Battery,” on both laptops. The Intel-based laptop tended to have occasional high-boost clocks, which led to short spikes in battery discharge rates.
After these runs, the reduction in the Prestige 14’s battery wasn’t as noticeable. For those who mostly do short, light boosty work, any disparity between Intel and AMD rival CPUs won’t be as apparent.
It’s not like Intel is trying to hide its power consumption. Look at this slide below from its presentation when it originally launched its Tiger Lake last year.
In its presentation, Intel basically was already saying Ryzen’s performance is heavily nerfed just based on the wattage the chip consumes vs. the wattage the Core i7 consumes. Of course, Intel doesn’t show you that more wattage used also means less available battery life.
Who’s right—Intel or Ryzen?
If you’re looking for undisputed winners and losers, you’re not going to find them in this story. Intel’s 11th-gen CPUs and AMD’s Ryzen 5000 mobile CPUs are showing different philosophies in how to build the best consumer experience.
With Tiger Lake, Intel seems to buy into the concept of increasing performance perception by giving you a very short boost to keep the laptop as responsive as possible—even when on battery. You launch Word or Chrome and start browsing, and the laptop will spike up to very high clock speeds, and very high and short-duration wattage use.
The weakness in Intel’s approach, obviously, is the sacrifice of battery life to get that responsiveness. If you want to mash the pedal all the time and eat up your battery at the highest performance—go right ahead.
Ryzen and the laptops we’ve seen so far with it, seem to favor a far more conservative approach—sacrificing performance to get as much run time as possible, all of the time. That high boost response Intel give you is great—but not if it means you’ve eaten up your battery to get there.
The weakness in AMD’s approach, at least implemented here, is dampening performance all of the time to save the battery. In our testing, we never got the same performance out of the ZenBook and Ryzen 7 on battery as we could when plugged in. That’s great—if everyone’s goal is extending the battery life. But some people truly want or need to crank it up, which runs counter to that slow-and-steady scenario.
The short answer to the question we started with is yes, Ryzen, even in the newest Ryzen 7 5800U, suffers—sometimes greatly—when running on battery in the Asus ZenBook. And yes, to be fair, we have to say the Core i7-1185G7 in the MSI Prestige 14 doesn’t give up performance on battery—but it drains that battery dry much faster too.
In the end, chose the philosophy that works best for what you need in your laptop, and drive on.