Asus ROG Zephyrus Duo 15 GX550 review: Two screens and a whole lot of speed

The Asus ROG Zephyrus Duo 15 GX550 is a dual-screen gaming laptop that’s learned a thing or two. It has a few predecessors, most recently the HP Omen X 2S 15 and Asus ZenBook Pro from 2019. But auxiliary screen sizes have been the limiting factor. The ZenBook Pro upped the ante with a much larger screen, for example, but it still lay flat, which made viewing angles a pain in the neck.

With the eye-catching—and blisteringly fast—ROG Zephyrus Duo 15 GX550, Asus takes the same small-screen concept from the ZenBook Pro and uses a folding mechanism to tilt the screen up about 20 degrees as you open the lid. That tilt both increases visibility and allows for a more efficient cooling path through the laptop. Pretty slick. And pretty expensive ($3,699 from Asus.com). But being the first at your LAN party with a dual-display gaming laptop must be worth something.

This review is part of our ongoing roundup of the best gaming laptops. Go there for information on competing products and how we tested them. 

Gordon Mah Ung

ROG Zephyrus Duo 15 GX5550 Specs

The Asus ROG Zephyrus Duo 15 GX550 is about medium-sized for a gaming laptop, with very few compromises in features. Here are the details: 

CPU: Intel 10th gen 8-core Core i9-10980HK with liquid metal thermal interface material

GPU: Nvidia GeForce RTX 2080 Super Max-Q

RAM: 32GB DDR4/3200 in dual-channel mode

Displays: 15.6-inch, UHD 4K 60Hz factory-calibrated 100 percent Adobe RGB panel with support for G-Sync and Optimus; 13.4-inch x 7.4-inch 1920×550 touch screen.

Storage: Two 1TB Samsung PM981 NVMe M.2 in RAID 0

Networking: WiFi 6, Realtek Gigabit ethernet

Size: 14.1 x 10.5 x 0.8 inches. 

Weight: Asus lists the laptop as 5.29 pounds, but our scale put it closer to 5.6 pounds, with another 2 pounds for the 240-watt power brick.

The best way to describe the fair assortment of ports is with photos. On the left you find a dedicated charging jack for the 240-watt power brick and two analog audio ports.

Gordon Mah Ung

With the left side pretty bare, Asus fortunately makes good use of the back of the laptop by giving you Gigabit ethernet, USB-A, and full-size HDMI 2.0.

Gordon Mah Ung

The right side gives you two USB-A and Thunderbolt 3. We would have liked to see a card reader. The good news is the Thunderbolt 3 jack supports USB Power Delivery, so you can leave the chunky 240W brick at home and just use a USB-C charger for light-duty tasks.

Gordon Mah Ung

Keyboard and trackpad

The per-key RGB keyboard is pretty typical of gaming laptops. The layout makes few compromises. As a gaming laptop, the space bar is wider on the left to accommodate those who hold their hands at extreme angles while gaming.

Gordon Mah Ung

The trackpad is an offset variety. It takes some getting used to, but we understand because a gaming laptop should really be used with a mouse most of the time. A long tap on the upper left corner turns on a virtual ten-key feature, which could be useful for someone maybe practicing for the professional Microsoft Excel gaming scene. 

Gordon Mah Ung

No webcam. Really.

We have to mention the elephant in the room: no webcam. Again. This is the second ROG laptop we’ve seen without a webcam which, viewed in a Zoom video chat world, seems like the biggest head slap this side of Taipei. We suspect that when this laptop was sketched out a year or two ago, few thought anyone would care if the webcam went overboard. The shift to remote working has forced us all to care about this former afterthought.

Gordon Mah Ung

Construction

We don’t typically get into the construction details weeds of a laptop, but the unique ROG Zephyrus Duo is worthy of it. For you upgraders, you can see in the image from Asus below two M.2 slots (both of which are populated in our RAID configuration) and a single SO-DIMM slot for memory. The second memory module fortunately isn’t soldered in, but it is on the other side of the motherboard, so any upgrades would require major disassembly. Those cut-outs on the bottom left and right are to make space for the tilt mechanism (more photos of that are below).

Asus

If you look more closely at the picture above, you can also see the CPU, which looks a little bit like a baseball field from an airplane. The gray area that would be grass in this case is where Asus clamps a containment system to keep the advanced liquid metal thermal interface material face in place and prevent it from potentially shorting out the laptop.

If you look at the picture of the ROG Zephyrus Duo’s cooler, below, you can see the fence to contain the liquid metal.

Asus

Why even take that risk over conventional thermal paste? If you think of the thermal interface material as the ketchup that mates the burger patty (CPU) with the bun (the cooler), Thermal Grizzly’s liquid metal compound is artisanal ketchup. Asus said its tests show about a 10-percent improvement in cooling over traditional thermal paste in laptops. Running cooler also means running quieter, and in our experience the ROG Zephyrus Duo is certainly quieter than most of the 10th-gen laptops we’ve seen with this much hardware, even when running hard.

Here’s a closer look at the “feet,” which are considerable bumps. That’s typically a good thing in a gaming laptop, as air flow is key to performance, but they’re also big because they’re hollow, to accommodate the hinge and tilt mechanisms.

Gordon Mah Ung

Lest you think the tilting mechanism will break, Asus emphasizes that it’s a chunky piece of metal, which you can see below. It’s been designed to tilt the panel up to a fixed angle while letting you continue to adjust the primary display’s angle.

The secondary panel itself is built of an alloy rather than plastic to keep it rigid (the laptop’s body is a magnesium alloy). Finally, if you happen to get your mouse or power cable jammed under the second screen, Asus said it would take a considerable amount of force to break.

For kicks we put the laptop’s own power cord under one corner and attempted to close the lid. We stopped as we felt the cable’s resistance, and nothing broke or snapped. That doesn’t mean you can’t break it, but it’s not as delicate as you might think.

Asus

Is the second screen worth the hassle?

All this work Asus has put into the ROG Zephyrus Duo would be meaningless if it weren’t worth the effort to have a second display. The primary display in our case is a 15.6-inch 60Hz 4K panel. It’s factory-calibrated, G-Sync-certified, and can hit 100 percent of Adobe RGB. It’s not particularly bright at a measured 300 nits. Asus offers this as a compromise for those who want to do content creation on the laptop. That’s fine, but for a gaming laptop, we think the other option might be better: a 300Hz 1080p display.

The ScreenPad Plus is where the action is. If we wanted to monitor the GPU’s thermals, the CPU’s clock speed, or simply put a second document within eyeshot, having the second panel is, well, as great as having it on your desktop. 

The gaming experience isn’t perfect, though. If you’re in a game and touch the second screen to adjust something or scroll a window–or advance to the next YouTube video–Windows changes focus from the game, and you’ll have to Alt-Tab to get back to the game. This is a shortcoming of Windows, not the ROG Zephyrus Duo. To prevent that from breaking your game experience, Asus added a button in the Armoury Crate application that lets you easily disable the touch experience.

Most of our multi-monitor experience is side-by-side. The bottom-and-top configuration took some getting used to. That may be our mousing habits though, as we tend to ride the bottom border of Windows like a guardrail. With the top-and-bottom experience, the cursor would just go to the second screen, and it would take us a few moments to find it again.

Asus’ Armoury Crate and other touch apps first introduced with Zenbook Duo are very polished. We’d say this is likely the best multi-screen experience on a laptop today.

Keep reading for performance benchmarks.

ROG Zephyrus Duo Testing

For performance testing Asus recommends using the Armoury Crate utility to switch from its default setting of Performance to Turbo. We actually tested both, as many people never ever switch out of default mode.

The ROG Zephyrus Duo is the first laptop we’ve tested that has been confirmed to have Nvidia’s Dynamic Boost features. Dynamic Boost is supposed to shift power intelligently between the CPU and GPU based on the gaming load. If, for example, a game is heavy on graphics (and most are), the GPU will ramp up while the CPU will ramp down. If a game is dependent on CPU, it should ramp up while the GPU ramps down.

Gordon Mah Ung

ROG Zephyrus Duo 15 CPU Performance

Our first benchmark is Maxon’s Cinebench R15, which measures a CPU’s performance rendering a 3D model. It’s nearly a pure CPU load, and more cores are better.

The result is actually spectacular when you compare it to the other top Intel-based laptops. The ROG Zephyrus Duo sticks close to them despite being almost a third lighter and half the bulk too. We’re seeing performance a little faster than the Acer Predator Helios 700, which weighs 10 pounds and features a slide keyboard to improve airflow.

The better comparison is against other 8-core thin and light gaming and work laptops, which are left eating the dust of the ROG Zephyrus Duo. 

And yes, we will point out just how impressive the Ryzen 9 4900HS is in the ROG Zephyrus 14.

IDG

To measure how the Zephyrus Duo performs in lighter tasks, we use Cinebench R15 again, but set to use a single thread. As is often the case with this test, it’s mostly a tie. You’d likely never tell the difference in daily use between the number-10 laptop on this list and the number 1. If all you care about is single-threaded performance for daily use—these are all equally good.

IDG

Our next test stresses the CPU for a longer period to see how it handles itself as it gets hot. We take a 30GB file and encode it using to Android TV preset, using an older version of the free HandBrake utility. The test used to take in excess of 45 minutes when we first adopted it four years ago, but we’re down to basically 20 minutes with modern laptops.

Here, we see the Asus ROG Zephyrus Duo perform in the neighborhood of laptops almost twice its weight. It’s almost 10 percent faster than the MSI GS66 Stealth which features the same CPU. The GS66 is about a pound lighter, but both are definitely in the same neighborhood versus the 11-pound Acer Predator Helios 700. That leading Alienware Area 51m R1 actually features a desktop Core i9-9900K. 

IDG

Zephyrus Duo 15 Gaming Performance

Moving to graphics performance, we’ll kick this off with UL’s 3DMark Time Spy, a synthetic benchmark that lets us separate pure graphics performance from CPU performance. Games are always useful for gut checks, but for a repeatable and accurate test, 3DMark is hard to beat.

One pattern we’ve noticed with recent thin-and-light gaming laptops is the importance of thermal management. The default performance can be pretty similar, but they start to differentiate when run in their “Turbo,” “Extreme,” or whatever high-octane performance profile the laptop maker offers. In that setting, the ROG Zephyrus Duo doesvery well. The 8-pound Alienware Area 51M R1 and the 11-pound Predator Helios 700 heavily flex their muscles here because they simply have much larger bodies to pack in more cooling and power delivery.

IDG

The ROG Zephyrus Duo does slightly underperform in default mode, but Time Spy is somewhat of a lighter load today and we suspect that to be the issue (which we’ll discuss later).

We wanted to try something more forward-looking so we also run 3DMark’s Port Royal, which measures Ray Tracing Performance. On its default setting the ROG Zephyrus Duo is essentially dead-even with the thinner and lighter MSI GS66 Stealth. That’s no surprise, as both laptops on default are held to their factory limits on the graphics cards. 

Set the Zephyrus Duo to its Turbo setting, though, and we see almost a 16-percent improvement in the Port Royal score.

IDG

3DMark’s Port Royal only measures ray tracing performance in reflections and shadows. For a view into the future, we ran the fully path traced version of Quake II RTX, which reinvigorates the 23-year-old game with future looking graphics.

In Quake II RTX we also see a fairly compressed finish between all of the gaming laptops here, which we expected. Even though it’s a 23-year-old game, the techniques it uses are simply brutal. That green bar on top is when the ROG Zephyrus Duo is on its Turbo setting and the GPU—for the most part—is allowed to run more freely. The result is about a 16-percent improvement in performance.

IDG

We also ran the challenging Red Dead Redemption 2, with the ROG Zephyrus Duo set to 1920×1080 and balanced graphics. We saw 77 fps out of it on its stock setting and an 8.5-percent increase in performance by switching to the Turbo mode. Basically most heavy-duty graphics and gaming loads and moderately heavy go like hell on the ROG Zephyrus Duo. 

But we still run older games, and that’s where we hit a snag. Running the seven-year-old Rise of the Tomb Raider we expected performance to be stellar, but we confusingly saw frame rates closer to that of a system with a GeForce GTX 1660 Ti.

IDG

We tried running the benchmark with the second panel switched off and double-checked that our unit was on AC, but we could not resolve our issue. Looking through recorded numbers for the extremely lightweight 3DMark Sky Diver test we also saw unexplained weirdness.

This shouldn’t be happening. Below you can see the performance of the MSI GS66 set to its default “Balanced” and its “Extreme” setting. You can also see XPG’s Xenia 15, which we’re in the process of reviewing. It features a hardware button to swap among a Power Saver Mode, a Balanced Mode, and a Performance mode. Like the MSI, the XPG laptop performance is where we expected, but with a bigger boost from Balanced to Performance as it’s slightly thicker and isn’t quite as thermally limited by its parts. 

IDG

The XPG Xenia 15, when set to its Power Saver mode, locks down the CPU and GPU clock speeds and power consumption to extend battery life. All this is expected.

The ROG Zephyrus Duo, however, just gets plain weird. Again, we see far substandard graphics and CPU performance. The bizarre swing going from its default Performance to Turbo just makes no sense.

Like most 3DMark tests, Sky Diver will first run two graphics tests intended to measure the GPU. Then it will run a simulated game physics test to measure CPU performance. 3DMark is reporting that moments after the physics test is kicked off, the CPU will spike up above 4GHz, and then dive down to 2.5GHz for a while before climbing back out of the valley.

While you might think this is just our unit, the truly blistering performance everywhere else makes us think it isn’t. What’s the issue? Nvidia’s Dynamic Boost or Asus’ own algorithm? We won’t know, but we are continuing to work with Asus to resolve it. We’re 90 percent sure this is nothing more than the result of the early algorithms and can be addressed in future updates.

ROG Zephyrus Duo Battery Life

Our last test is battery life. For that we loop a 4K video using Windows 10’s super-efficient Movies & TV player. We put the laptop into airplane mode, with its display set at 250 to 260 nits. We also plug in a set of earbuds to try to reduce the impact of the audio subsystem on results. 

The ROG Zephyrus Duo will automatically kick down to Silent mode when on battery to conserve power, but it does not turn off the second screen. Because most people will switch off the second panel to watch a movie on a trip, we turned it off as well (a button just above the trackpad lets you easily do this).

The result was a respectable six-plus hours off its 90-watt-hour battery. Both the MSI GS66 Stealth and Gigabyte’s Aero 17 get closer to 7 hours, but that’s not a huge difference like you’d see with, say, Dell’s new XPS 15 9500, which hammers out more than 10 hours.

We also ran the same video test with the second screen turned on, but dimmed considerably. We saw about 4 hours of battery life.

Keep in mind that our video test, while realistic, can be considered a light test. Switch on the Wi-Fi and browse the web or run Office, and you can expect to take a third or more off battery life. Fire up a video editor or game, and you can expect no more than an hour or two, realistically. 

Basically, battery life seems mostly in line with a gaming laptop experience, unless you run both screens at once.

IDG

Conclusion

There’s a lot to unpack with the ROG Zephyrus Duo, but we’ll start with the performance. If you believe us that the subpar performance on light gaming tasks is probably a temporary issue, the takeaway is that it’s very fast for its weight and stature. We suspect as we see another three or five 15-inch laptops with similar part combinations, most will settle down closer to the Gigabyte Aero 17 or MSI GS66 Stealth in performance. Asus’ use of liquid metal and better cooling paths simply makes it the laptop to beat, and we’re not sure others in the same class of laptop can do that.

The second point we want to touch on is the price. As configured, our review unit pushes $3,699 on Asus.com. That’s practically Apple pricing (except you’re getting a boatload more performance and features), but gaming laptops are not getting cheaper. The far more conventional MSI GS66 Stealth, with a 300Hz panel and mostly similar parts, is $3,000. The Gigabyte Aero 17, with an arguably better 10-bit, HDR 400 4K screen, plus an 8-core Core i7-108750H, GeForce RTX 2070 Super, and half the RAM and far less storage, is $2,700.

The decision comes down to how much value that second screen adds. That’s very much a personal choice, but we have to say as multi-monitor users we find it invaluable. Whether it’s to view reference documents while editing in the main window, watching a video while working, or monitoring the team statistics of the players you’re facing in a match, we could never go back to a single screen on our desktop. With Asus’ ROG Zephyrus Duo 15 GX550, now you don’t have to do it with a laptop, either.

Gordon Mah Ung