ASUS Zenbook Duo (UX8406) vs. Lenovo Yoga Book 9i (Gen 9): Which dual-screen laptop is better for you?

Dual-screen laptops have been around in some shape or form for a couple of decades, but the form factory only really kicked off in a major way with Lenovo's 2016 Yoga Book and Yoga Book C930 in 2018. The Surface Neo ended up being a 2019 fantasy, but the form factor hasn't died off.

The ASUS Zenbook Duo (UX8406) and Lenovo Yoga Book 9i (Gen 9) both launched in 2024, and they're both impressive dual-screen laptops featuring OLED touch displays, wireless keyboard attachments, and Intel's latest Core Ultra processors (CPU) complete with Neural Processing Unit (NPU) for improved efficiency in AI tasks.

While both laptops offer a similar form factor, they're not actually as closely matched as you might imagine. The Zenbook Duo is more affordable and offers more powerful H-series CPUs, whereas the Yoga Book 9i is more expensive but comes with a higher-end design and a soundbar hinge.

These laptops are ideal for multitasking, and professionals or creators will stand to benefit the most. If you're trying to decide which dual-screen laptop is best for you, I've compared the Zenbook Duo (UX8406) and Yoga Book 9i (Gen 9) right here to help you get the perfect PC.

ASUS Zenbook Duo vs. Yoga Book 9i: Specs

Before we get too far into the breakdown of the differences and similarities between these two laptops, I'd like to lay out the specifications available in each device. 

ASUS Zenbook Duo vs. Yoga Book 9i: Price and availability

The ASUS Zenbook Duo starts at about $1,500 for a model with Intel Core Ultra 7 155H CPU, integrated Intel Arc graphics, a 1TB SSD, 16GB of LPDDR5x RAM, and the dual FHD+ OLED touch displays.

You can also spec up to an Intel Core Ultra 9 185H chip with 32GB of RAM, 1TB SSD, and 2.8K OLED displays for only about $200 more. The Zenbook Duo is, at the time of writing, quite hard to find. You can sign up for in-stock notifications at the Asus website. It is also currently available to buy from B&H.

Lenovo's Yoga Book 9i for 2024 is readily available at Lenovo's official store, starting at $1,980. This model includes an Intel Core Ultra 7 155U CPU, integrated graphics, 16GB of RAM, 512GB SSD, and dual 13.3-inch 2.8K OLED touch displays.

Lenovo gives you the ability to add up to 32GB of RAM and a 1TB SSD, which pushes the price up to about $2,067.

If you're looking to buy the Yoga Book 9i and want the latest model, be sure that you're seeing models with Intel Core Ultra CPUs. Lenovo still has the previous model with 13th Gen U-series chips for sale at a bunch of retailers.

ASUS Zenbook Duo vs. Yoga Book 9i: Design and features

The Zenbook Duo is a 14-inch dual-screen laptop that could easily be mistaken for a more traditional device; that is, if it wasn't quite so thick. Its removable keyboard and touchpad lives between the two displays when the device is closed up, resulting in about 0.78 inches of overall thickness. A built-in stand on the back of the laptop also adds to the weight.

The Yoga Book 9i (Gen 9), on the other hand, is a 13.3-inch device measuring about 0.63 inches thin when closed. However, its keyboard and origami stand live separately from the laptop when in transit; it's not as elegant of a solution, and some users will likely opt for the extra weight and thickness just to have all the pieces come together in the Zenbook Duo.

Both laptops are built to a high standard, with the Zenbook Duo reminding me more of a business laptop. Its hinge system creates an offset between the two displays, but it can be used in horizontal or vertical modes. It might not feel as stable with the displays side-by-side, but it really gets the stacked setup right.

Lenovo chose to incorporate the soundbar hinge from its Yoga 9i into the Yoga Book 9i, resulting in a more seamless look without an offset between displays. The screens can be rotated completely around, whereas the Zenbook Duo only opens to 180 degrees.

The soundbar hinge provides more flexibility, and it also pumps out stellar audio. There are four total speakers for 8W total in the Yoga Book 9i, which easily beats the Zenbook Duo's two speakers. That's not to say audio from the Duo isn't also great in its own regard. Dolby Atmos support helps boost sound quality with dynamic adjustments, and there's plenty of volume.

As for the webcam, it's one area where the Zenbook Duo falters. The 1080p camera just isn't that great, even if it does offer an IR sensor for facial recognition, and it lacks a shutter. The Yoga Book 9i's 5MP camera, also with an IR sensor, should do a better job for video conferencing; plus, it has an e-shutter with a switch on the side of the PC.

Lenovo chose to stick with three Thunderbolt 4 ports for the Yoga Book 9i, which will likely cramp some workflows if you aren't using one of the best Thunderbolt docks. Asus offers one less Thunderbolt 4 port, but it adds HDMI, USB-A 3.2 (Gen 1), and a 3.5mm audio jack. Neither laptop is a connectivity master, but at least the Zenbook Duo has those extra hookups without having to add a dongle.

ASUS Zenbook Duo vs. Yoga Book 9i: Typing and pointing

The Yoga Book 9i has a separate Bluetooth keyboard portion that lives apart from the laptop. When the laptop is open, the keyboard can be placed on the bottom screen, which itself will display a digital touchpad. If you're using the keyboard wirelessly on your lap or in front of the PC, you will need an external mouse for pointing as it lacks an attached physical touchpad. The keyboard also lacks a backlight.

As mentioned, the keyboard needs to be carried separately from the rest of the laptop when you're on the move.

The ASUS Zenbook Duo's keyboard primarily lives between the two halves of the laptop, set in place on strong magnets and connected with POGO pins. It features 1.4mm key travel, backlighting, and a physical touchpad, with Bluetooth connectivity when you peel it away from the bottom screen.

Typing feels great on this keyboard whether it's attached to the bottom display or sitting in your lap. It's sturdy enough that there's hardly any flex, and the touchpad doesn't creak or rattle even when tapped. If you hate using a digital touchpad or an external mouse, this should be a major factor in your decision.

ASUS Zenbook Duo vs. Yoga Book 9i: Displays

ASUS offers two different resolutions for the Zenbook Duo's dual OLED displays. More affordable models come with 14-inch screens with 1920x1200 (FHD+) resolution, but you can bump that up to a 2880x1800 (2.8K) resolution for a crisper picture.

The FHD+ screens feature a 60Hz refresh rate, 400 nits brightness (jumping to 500 nits with HDR enabled), 100% DCI-P3 color, and inking support for the included pen. VESA DisplayHDR 500 True Black certification is also included.

The 2.8K screens are almost the same beyond the resolution bump, though the refresh rate ricks up to 120Hz.

On Lenovo's side, the Yoga Book 9i (Gen 9) comes with two 13.3-inch OLED touch displays, each with a 2880x1800 (2.8K) resolution. They have 100% DCI-P3 color, 400 nits brightness (jumping closer to 500 nits with HDR enabled), Dolby Vision support, and VESA DisplayHDR True Black certification. They do not, however, offer the same 120Hz refresh rate as the Zenbook Duo, falling back on 60Hz instead.

ASUS Zenbook Duo vs. Yoga Book 9i: Performance and battery

It's important to note that while the ASUS Zenbook Duo and Yoga Book 9i for 2024 both feature Intel's Core Ultra CPUs, the former laptop employs the more powerful H-series chips while the latter sticks with a U-series option.

The Zenbook Duo is available with Core Ultra 7 155H or Core Ultra 9 185H chips, the former running at a 28W base TDP and the latter at a much higher 45W base TDP. The Yoga Book 9i has a Core Ultra 7 155U chip running at a 15W base TDP. 

In our testing, the Zenbook Duo's Core Ultra 9 chip put up strong numbers in benchmarks, which translate into snappy everyday performance. Battery life is also impressive, even with two OLED screens, and you should easily be able to get through a full workday if you're primarily using just one screen.

We haven't personally tested the Yoga Book 9i for 2024, but the U-series chip won't likely match the performance available from the stronger H-series CPUs. Battery life, on the other hand, will most likely be better due to the significantly lower power draw.

On the AI side of things, both of these laptops have an NPU inside for improved efficiency in AI tasks. They could be considered an AI PC depending on who you ask, though they both lack a Copilot button on the keyboard.

ASUS Zenbook Duo vs. Yoga Book 9i: Which should you buy?

In our ASUS Zenbook Duo review, Windows Central Editor Ben Wilson remarked that it's "a fantastic laptop that practically never faltered during my testing, leaving only a desire for a better webcam and an Ethernet adapter freebie thrown in the box." That's high praise for a laptop form factor that many people still consider a gimmick, and we include it in our best 2-in-1 laptops roundup.

It's not as sleek as the Yoga Book 9i, but many users will appreciate the full keyboard with a touchpad that lives between the displays. You don't have to worry about keeping a separate keyboard and stand nearby, and there's less chance that you'll feel the need to add an external mouse to the setup.

The Zenbook Duo's Core Ultra H-series CPUs can deliver more power at the cost of battery life, and its 2.8K OLED displays hit a 120Hz refresh rate for a smoother experience. Add all this up with a much lower starting price, and you have a dual-screen laptop that is likely going to appeal to a lot more people.

The Yoga Book 9i remains a great choice for those who want a high-end dual-screen laptop with a thin and premium design, soundbar hinge, and a higher-quality webcam. Its CPU won't offer as much power, but that should translate into better battery life. 

The higher cost will likely drive a lot of people toward the Zenbook Duo, but admittedly, there is just something about the high-end Lenovo design that will pull in a lot of customers.