ASUS Zenbook Prime UX31A Review

Laptop Mag Verdict

The ASUS Zenbook Prime improves upon one of the best Ultrabooks by adding a 1080p IPS screen, backlit keyboard and speedy 3rd generation Core i7 processor.


  • +

    Very bright and sharp 1080p IPS screen with wide viewing angles

  • +

    Fast 3rd generation Core i7 processor

  • +

    Improved keyboard comfort with built-in backlight

  • +

    Clear audio from Bang & Olufsen speakers


  • -

    Touchpad can be erratic

  • -

    Relatively slow SSD

  • -

    Webcam struggles in low light

Why you can trust Laptop Mag Our expert reviewers spend hours testing and comparing products and services so you can choose the best for you. Find out more about how we test.

ASUS's original Ultrabook was the first ultraportable laptop to give the MacBook Air a run for its money, but it ultimately fell short. The new ASUS Zenbook Prime UX31A (starting at $1,099, $1,499 as configured) is a sequel to truly get excited about. This successor has the same sleek spun metal design and offers lots more eye candy on the inside with a new 1080p IPS display. The Prime also adds a comfier backlit keyboard and a third-generation Intel Core processor for a serious speed boost. Do all of these ingredients add up to the best Ultrabook yet?

[sc:video id="9kdXA1cTr_bWiXA03W1H0rAqHzNZjfqv" width="575" height="398"]


Click to EnlargeFrom the outside, the Zenbook Prime looks like a dead ringer for its predecessor -- and we're not complaining. The 3-pound Ultrabook is just as elegant as ever, thanks to a dark brushed metal lid with a subtle circular pattern that emanates from the ASUS logo. (It's a little darker than the UX31). The inside and bottom of the Prime sport a lighter brushed aluminum finish with a vertical pattern.

The overall construction feels as solid as ever, even if the corners are a bit sharp for our tastes. We also find the lid easier to open on the UX31A than the UX31.

Click to EnlargeAt 13.3 x 8.9 x 0.44-0.66 inches (our measurements), the Zenbook Prime has the same dimensions as the original UX31. The HP Envy Spectre XT (12.9 x 8.7 x 0.6 inches) and Dell XPS 13 (12.4 x 8.1 x 0.7 inches) manage to cram a 13-inch display into a 12-inch chassis using a thinner bezel. Nevertheless, we don't think users will mind the slightly wider and taller body on the ASUS. It's easy to slip into a bag or backpack, and will easily fit on an airline tray.

Just like the original, the Zenbook Prime features a speaker integrated into the display hinge, and a very large touchpad sits underneath the keyboard. The layout is now black instead of silver, making the keys easier to read.

Our only real quibble with the design is that the display sometimes flopped back, which happened during a bumpy bus ride and on a couple of occasions when picking the Ultrabook up. But the lid doesn't fall back very far.


Click to EnlargeAll the keys are in the same place on the Zenbook Prime, but they feel a lot better. That's because ASUS ripped out the old silver layout and added black keys with much improved travel (12 percent better key cap travel distance). Typing this review felt fluid and fast on the UX31A, compared with the mushier experience on the UX31.

Just as importantly, ASUS made this keyboard backlit, making the layout much easier to see in our dimly lit living room.

Click to EnlargeYou can also adjust the intensity using a function key combination. Annoyingly, the right side of the keyboard didn't get as bright as the left, but ASUS assured us that final production units shouldn't have this issue.

So what did ASUS not fix? That would be reversing the function row to make them direct access keys. We'd much prefer adjusting the volume, brightness and other settings without having to execute a key combo.


Click to EnlargeThe good news is that the Zenbook Prime's 4.1 x 2.8-inch Elan touchpad can provide a satisfying navigation experience. The bad news is that we had to tweak some settings to make that happen. At first the cursor was too unwieldy, especially when typing, and we would accidentally type over our work. However, once we disabled both tapping and drag and drop in settings, the UX31A was less temperamental.

Most multitouch gestures worked smoothly right out of the box. We quickly three-finger flicked through photos, and three-finger flicking up for switching windows and flicking down to show the desktop were both responsive. Pinch to zoom and rotate also worked well.

Two-finger scrolling was inconsistent in our testing, however. On applications such as WordPad we scrolled smoothly and quickly, but the same gesture was sluggish in both Chrome and Internet Explorer.


While slightly warmer than its predecessor, the UX31A managed to stay pretty cool during our tests. After streaming a Hulu video at full screeen for 15 minutes, the touchpad measured 83 degrees Fahrenheit, the space between the G and H keys was 91 degrees, and the middle of the underside was 92 degrees. All are less than what we consider uncomfortable: 95 degrees.


Click to EnlargeIf you have the means, splurge for the $1,399 configuration of the Zenbook Prime. Not only is this 1920 x 1080 matte panel sharper than the MacBook Air--and most other 13-inch laptops--it's superbright and offers generously wide 178-degree viewing angles.

When we hit the UX31A with our light meter, the display averaged 423 lux, which is brighter than the older UX31 (391 lux) and well above the ultraportable average (219 lux). The Zenbook Prime also handily beats the MacBook Air (285 lux) and Samsung Series 9 13-inch (355 lux).

To compare picture quality, we put the Zenbook Prime and MacBook Air side by side and played "The Avengers" trailer in full HD. We preferred the warmer colors on the ASUS, which made skin tones look more natural and explosions pop more. In addition, the Prime's matte screen allows for wide horizontal and vertical viewing angles, on a par with the Air.

Is 1080p on a 13-inch notebook overkill? Not to us, because you get full HD video playback and the ability to see more content on screen when surfing the Web and when snapping two windows side by side. The trade-off is that that you often need to zoom in to read text.


Powered by Bang & Olufsen's ICEPower technology, the speakers embedded in the Zenbook Prime's hinge delivered moderately loud and clean-sounding audio. When streaming Fun's "We Are Young," Nate Ruess' vocals had a nice warmth. However, Coldplay's "Speed of Sound" sounded louder and fuller on the UX31 than the Zenbook Prime.

The sound effects in "Angry Birds" came through loud and clear when we played the game on the Chrome browser, as did the audio on "The Avengers" trailer. We just wish the audio controls were more robust; the UX31A only has the standard Windows enhancements.


Click to EnlargeThe Zenbook Prime keeps ports to a minimum, with a USB 3.0 port, headphone jack and SD Card reader on the left side. A micro HDMI, mini VGA port, second USB 3.0 port and power jack line the right side. You're going to have to spring for an HDMI or VGA adapter if you want to output video to an external display. By comparison, the slightly thicker UX32 will have a full-size HDMI port and three USB 3.0 ports.


Click to EnlargeThe Zenbook Prime's webcam is capable of capturing 720p video, but you'll need a fair amount of ambient light to get a bright picture. When near a window, the blue in our shirt popped, but the background was fuzzy. When we merely swiveled our chair around away from the window, the picture got so dark we could barely make out our face. We're also not fans of the Lifeframe software. The controls are too small.


A 3rd-generation 1.9-GHz Intel Core i7-3517U processor, 4GB of RAM, and 256 GB solid state drive under the hood really make this ultraportable fly.

On the PCMark07 test, which measures overall performance, the Zenbook Prime scored 4,989, which is nearly double the ultraportable category average (2,593) and well above the UX31 (3,606) and Dell XPS 13 (3,521). Then again, you should expect faster performance from an Ivy Bridge Core i7 CPU withn an SSD. The only lightweight laptop we've tested that comes close to the Zenbook Prime is the Eurocom Monster (4,299), which has Ivy Bridge and discrete Nvidia graphics.

The Zenbook Prime took 4 minutes and 59 seconds to complete the LAPTOP Spreadsheet Macro Test, in which we use OpenOffice calc to match 20,000 names with their addresses. That showing bests the the HP Folio 13 (6:44), UX31 (5:50) and the IdeaPad U300s (5:05).

So how about transcoding video? The UX31A took 30 seconds to convert a 5-minute 1080p video to an iPhone friendly format using Cyberlink's MediaEspresso. That time is actually a bit behind the Dell XPS 13 and Samsung Series 9 15-inch (both 29 seconds) but ahead of the Folio 13 (41 seconds). However, our pre-production version of the Zenbook Prime didn't have Intel's latest video drivers; we expect performance to improve once those become available.

The SanDisk SSD inside the Zenbook Prime is faster than your typical hard drive, but not as speedy as other Ultrabooks. The notebook duplicated a 4.97 GB folder of multimedia files in 1 minute and 39 seconds for a rate of 51.4 MBps. That's faster than the ultraportable average (46 MBps), but slower than the older UX31 with an ADATA SSD (98 MBps). By comparison, the XPS 13 notched 137.5 MBps and the Air 127 MBps.

Boot and Wake Times

Thanks to the 256GB SSD, booting into Windows 7 took the UX31A only 23 seconds, which is faster than the Dell XPS 13 (27 seconds), UX31 (29 seconds) and HP Folio 13 (26 seconds). The Air is still faster at 17 seconds, but this notebook will never keep you waiting. That also applies to wake from sleep. Upon lifting the lid, the Zenbook Prime sprung back to life within 2 seconds.


Intel's third-generation Core processors promise increased graphics performance via Intel HD Graphics 4000 technology, and the Zenbook Prime delivers just that. When playing "World of Warcraft," the Ultrabook notched 52 frames per second at 1366 x 768 resolution. That's considerably better than the UX31 (40 fps) and category average (36 fps). Even on 1080p resolution, the Prime achieved a playable 36.3 fps with the settings on Good.

On 3Dmark06, the UX31A turned in an impressive score of 5,021, which beats the MacBook Air in Boot Camp mode (4,236) and every other Ultrabook we tested, most of which have scored in the 3,500 range.

If you want more graphics muscle, ASUS will also offer a version of the Zenbook Prime with the Nvidia GT620M discrete GPU with 1GB of video memory.

Battery Life

Click to EnlargeThe original Zenbook's 50-watt-hour battery lasted a fairly good 5 hours and 58 mintues on a charge. The new Zenbook Prime lasts 6 hours and 28 minutes, or a half-hour longer. That's impressive endurance given that this configuration uses a faster Core i7 processor and the older UX31 had a Core i5. The 13-inch MacBook Air lasted 6:25 and the XPS 13 and 5:46. However, the HP Folio 13 supplies nearly 8 hours of juice (7:50), while the Toshiba Portege Z835 lasted 6:48, albeit with a slower Core i3 CPU.

Software and Warranty

Click to EnlargeOut of the box, the Zenbook Prime will hit you with two types of pop-ups pretty consistently unless you act on them. One is McAfee Internet Security and the other is ASUS Webstorage, which provides 2GB of free space for one year. We say activate the security and stick with Dropbox, Google Drive or Windows SkyDrive instead of opting for a whole new service. Other ASUS programs of note include the Vibe Fun Center for accessing Music, Games and Books, Instant Connect for taking your notebook online via an Android smartphone and FaceLogon for logging on with facial recognition.

ASUS covers the Zenbook Prime with a one-year warranty that includes parts, labor, and one instance of accidental coverage as well as 24/7 support. See how ASUS fared in our our Tech Support Showdown and  Best & Worst Brands repots.

Configuration Options

The ASUS Zenbook Prime UX31A will start at $1,099 with a Core i5 processor and 128GB SSD. Stepping up to the $1,199 model gives you TPM security. Our $1,499 configuration adds a Core i7 processor and 256GB SSD. All of these models include a 1080p display.

ASUS will sell another version of the Zenbook Prime, the UX32A, starting as low as $799. For that price you get Core i3 performance and a 320GB hard drive with 24GB SSD and a 1366 x 768 screen. The UX32 line is slightly thicker but adds an additional USB port and full-size HDMI port.

Want an Ultrabook with discrete graphics? ASUS will also offer a $1,299 Zenbook Prime, the UX32 VD, with an Nvidia GT620M discrete GPU with 1GB of video memory. The company promises twice the performance of Intel's HD 4000 graphics along with Optimus support for automatic graphics switching to preserve battery life. However, you won't get an SSD at this price; it will be a 320GB or 500GB hard drive plus a 24GB SSD.


Click to EnlargeAfter testing the Zenbook Prime, it's clear that ASUS worked hard to improve its Ultrabook. Although the $1,499 price of our configuration isn't cheap, you get a sharper screen than the 256GB MacBook Air for $100 less. And the new backlit keyboard is much easier to type on than the previous Zenbook. Add in a faster 3rd-gen Core i7 CPU and longer battery life and ASUS has elevated its Ultrabook from a very good product to one of the best money can buy. The only drawbacks are a slightly wonky touchpad and relatively slow SSD. Overall though, the Zenbook Prime is our new favorite Ultrabook.

ASUS Zenbook Prime UX31A Specs

BluetoothBluetooth 2.1+EDR
CPU1.9-GHz Intel Core i7-3517U
Card Slots2-1 card reader
Display Size13.1
Graphics CardIntel HD Graphics 4000
Hard Drive Size256GB
Hard Drive Speedn/a
Hard Drive TypeSSD Drive
Native Resolution1920x1080
Operating SystemMS Windows 7 Home Premium (64-bit)
Optical DriveNone
Optical Drive Speedn/a
Ports (excluding USB)USB 3.0, mini-VGA, micro HDMI
RAM Upgradable to4GB
Size13.3 x 8.9 x 0.44-0.66 inches
Touchpad Size4.1 x 2.8 inches
USB Ports2
Video MemoryShared
Warranty/Support1-year parts and labor, 1-year accidental coverage (one occurrence), 24/7 Tech Support
Weight3 pounds
Mark Spoonauer
Responsible for the editorial vision for, Mark Spoonauer has been Editor in Chief of LAPTOP since 2003 and has covered technology for nearly 15 years. Mark speaks at key tech industry events and makes regular media appearances on CNBC, Fox and CNN. Mark was previously reviews editor at Mobile Computing, and his work has appeared in Wired, Popular Science and Inc.