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Asus ZenBook Prime UX31A review: Asus ZenBook Prime UX31A

The ZenBook Prime UX31A is everything the ZenBook UX31E should have been, and more. We have no hesitation in recommending this laptop if you truly want no-compromise performance in an ultrabook.

Craig Simms Special to CNET News
Craig was sucked into the endless vortex of tech at an early age, only to be spat back out babbling things like "phase-locked-loop crystal oscillators!". Mostly this receives a pat on the head from the listener, followed closely by a question about what laptop they should buy.
Craig Simms
6 min read

The ZenBook Prime is exactly what the first generation of ZenBooks should have been.


Asus ZenBook Prime UX31A

The Good

Lovely Full HD, IPS screen. Backlit keyboard. Great performance.

The Bad

Some light bleed from the bottom of the screen. Included USB to Ethernet adapter is USB 2.0 only. Battery life could be improved.

The Bottom Line

The ZenBook Prime UX31A is everything the ZenBook UX31E should have been and more. We have no hesitation in recommending this laptop if you truly want no-compromise performance in an ultrabook.

While it still inhabits a head turning, champagne coloured aluminium chassis, it's more than just an Ivy Bridge update. Asus' latest puts in a vastly improved, backlit keyboard and swaps out the Sentelic pad for an Elan, something that was done midway through production of the original ZenBook. The Elan experience is worlds better in tracking and reliability, and also enables the simultaneous-double-tap gesture, which is interpreted as a right click. The only issue we've found with the Elan pad so far is to do with old Windows help files (of .CHM format), where double finger scrolling for some reason also magnifies the page uncontrollably. It's an vanishingly niche problem, but nonetheless exists.

Other changes to the ZenBook include two USB 3.0 ports instead of one; and most importantly, an IPS 1920x1080 screen.


  • USB 3.0: 2
  • Optical: None
  • Video: Micro VGA (adapter included), micro HDMI
  • Ethernet: None
  • Wireless: Dual channel 802.11n, Bluetooth 4.0

It's about time that screens got decent, too. The superior viewing angles are immediately apparent, the gradation between colours significantly better. It identifies itself as being manufactured by CMN, which we can only assume is Chimei.

It has an obvious brown colour cast by default — white is definitely not white, grey is definitely not grey. Asus' Splendid tool comes in handy here; setting the screen to "My Profile" and the temperature to 6500K fixes the issue.

One thing that can't be fixed is the distinct points of light bleed along the bottom, very obvious when a dark screen is shown. While a certain amount of bleed from the bottom is common for laptops, it's disappointing from an IPS screen, considering it's meant to be premium.

By default, the screen is set at 125 per cent DPI, and it's likely most will want to keep it there, as text can seem a little tiny at 100 per cent. We can only imagine how squished the 11.6-inch version of the Prime will be, which also offers a Full HD screen. Just be aware that a huge amount of Windows apps don't properly scale with DPI settings, and so at 125 per cent, you may see some situations where text is overly huge and runs outside of element borders.

Inside is Intel's Core i7 3517U at 1.9GHz (which will turbo up to 2.4GHz), with 4GB RAM and a 256GB SanDisk U100 SSD. Despite all this, the cost is reasonable — AU$1799. Knock that down to a Core i5 3317U at 1.7GHz with a 128GB SSD, and suddenly you're at an even more affordable AU$1399. Both models contain Bluetooth 4.0 and 2.4GHz/5GHz wireless N.

Just like last time, Asus bundles in a laptop sleeve and USB to Ethernet adapter, which, to our disappointment, is still USB 2.0, greatly limiting the speed. While the chips exist, at the time of writing, there doesn't seem to be too many retail-ready USB 3.0 to Ethernet converters in the market. Given that there's no Thunderbolt port on the UX31A, one can't even take the Apple route. Within time this will likely be addressed, but it's disappointing Asus didn't take the lead on this one.

Asus also bundles a micro-VGA to VGA adapter, but don't expect the same treatment for the micro-HDMI port — that is up to you to fill the gap on.

Otherwise, there's a full-sized SD card reader and a headphone jack. It shares two MacBook Air weaknesses: there's no microphone jack, so you'll be using the inbuilt or USB mic, and when you run your hands over the lid surface during charging, a strange buzz runs down your fingers.

Application performance

Choose a benchmark: Handbrake | iTunes | Photoshop | Multimedia

Domination. The third generation Core i7 wipes the floor clean with the previous generation ultrabooks — while the Photoshop test does come out one second slower than the UX21E, we consider this within margin of error.

Battery life

It's worth noting Intel's addition of configurable TDP to Windows power profiles, thanks to Ivy Bridge. By default, things are set to 17W/2.4GHz on high power profiles, but clock to a low power profile and you'll drop to 13W, with an option of 1.9GHz or 1.0GHz as the ceiling. This could have the potential to lower battery times, but, overall, we saw worse performance than the original ZenBook. This is no surprise: it's powering a more dense, more colour accurate screen and a backlit keyboard.


The ZenBook Prime UX31A is everything the ZenBook UX31E should have been, and more. We have no hesitation in recommending this laptop if you truly want no-compromise performance in an ultrabook.

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