Asus ZenBook UX21

For so much promise, the ZenBook UX21 falls tragically short at one of the most important factors: human interaction. The touch pad, screen and keyboard make this one product you'll want to pass by — no matter how pretty it is.

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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.

The ZenBook UX21 surely is a beautiful sight. It's been a long time since we've been stopped by work colleagues, excited to see what we're holding.

The spun aluminium pattern on the lid is gorgeous, the interior brushed look even more so. It's truly an elegant piece of engineering.

Class leading, in some areas

It's not all looks, though: the SandForce-based ADATA XM11 128GB SSD found inside has the goods. It churns at a magnificent speed, and its inclusion at this price point is quite a coup. The ability to scale up to a 1.8GHz Core i7 2677M is also greatly appreciated, as is the small size of the power adapter. Like the MacBook Air, however, the UX21 picks up an odd ability in regards to power — if you brush your hand against the metal while it's plugged in and charging you get an odd buzz.

While not as fast as the full-sized SandForce SSDs, Asus' implementation still has plenty of grunt.
(Screenshot by CBS Interactive)

The included Bang & Olufsen speakers are rather excellent considering the size of the laptop they're in. They still distort at full volume and they certainly won't give you the balanced tone of a good set of headphones, but for the application both Asus and Bang & Olufsen deserve applause.

The laptop is joined by a few accessories, intended to make the MacBook Air's offerings look anaemic. A VGA adapter makes the bundle for legacy users, along with a laptop sleeve. The latter feels cheap, and looks it up close — still, it is a free laptop sleeve.

Missed opportunities

Asus also bundles in an Ethernet adapter, although it missed the chance to really give the competition a nudge, opting for a USB 2.0, 100Mb dongle. With a USB 3.0 port staring us in the face, completely capable of gigabit speeds, it seems odd to have not gone with gigabit.

Other things that could ease user experience have slipped past the eye of the QA officer as well, including the design of the power plug. Positioned far too close to the USB 3.0 port, the 90-degree design restricts movement and means that if something is plugged into the USB port, things get cosy and awkward rather quickly.

Finally, there's no backlit keyboard here. Asus has indicated this is a time to market thing, suggesting the next-generation ZenBook will likely be packing one of these.

Everything in life has a price

Sadly, the beauty of the UX21 only runs skin deep. Wonderful SandForce drive aside, the UX21 has some crippling problems, even once you update the Wi-Fi drivers to get past reception flakiness.

The first is the keyboard; an oddly mushy affair with high resistance, it drops letters frequently while typing. Even stabbing at each individual key with excessive force doesn't completely solve the issue.

The touch pad is equally terrible, which is to be expected: it's a Sentelic.

Erratic behaviour and terrible software is the hallmark of a Sentelic pad, and this one is no different. Grabbing a driver update ( from Asus' website helps to quell some problems, but it is still a largely frustrating pad to use, with multi-touch in particular proving highly inconsistent.

Sentelic can't even get the updating of the driver right, with Windows asking us if we wanted to run three separate executables each time we logged in, until we told it that yes, we trusted these strange files from the internet.

The UX21's 11.6-inch, 1366x768 screen is another sore point, with atrocious vertical viewing angles that will leave you feeling as if you've never gotten the monitor position quite right.

The final nail in the coffin is heat: if you use the ZenBook for word processing and web browsing, you'll likely never have an issue. But under heavy load, the rear of the machine near the hinge reaches scalding levels, making this definitely not a computer for your lap.

All of this is likely down to Intel's requirement that Ultrabooks attempt to hit a sub-US$1000 price point. Asus obviously decided early in the piece that the premium look and SandForce drive were in, and everything else had to be downscaled as a result.

We'd certainly be interested in a premium version of the UX21: something with a fixed keyboard, the Elantech pad found in the Acer Aspire S3, a better screen and heat management. We'd gladly throw a few hundred more onto the price to make it happen.


Handbrake encoding (in seconds)

(Shorter bars indicate better performance)

In this test we're encoding a 720p XviD file to H.264, a primarily processor-bound task. Interestingly, despite the Asus having a Core i7 and SSD, the more modest Core i5 units outdo it.

iTunes encoding (in seconds)

(Shorter bars indicate better performance)

Our iTunes test encodes two albums worth of AAC files to 224Kbps MP3s. It stresses both CPU and disk, allowing the SSD units to show their might against mechanical hard drive competitors.

Photoshop CS5 benchmark (in seconds)

(Shorter bars indicate better performance)

CNET Australia's Photoshop CS5 test applies many different filters to a series of RAW files, performs common tasks such as layer creation, image rotation and resizing, then exports to web. It hits all aspects of the system, and it's no surprise the ZenBook comes out on top here.

Multimedia multitasking test (in seconds)

(Shorter bars indicate better performance)

For our multimedia multitasking test, iTunes is set to encode to MP3 continuously while a Handbrake encode is run in the background; the time taken is when the Handbrake encode stops. Designed to punish the system, every extra bit of performance here counts, the Asus showing what it's got.

Battery life (time)

  • Heavy battery test
  • Light battery test

(Longer bars indicate better performance)

Our battery test comes in two parts: the heavy test, which loops a 720p video while the power profile is set to high performance, and the light test, which involves web browsing on a low performance power profile until the battery exhausts itself.

The ZenBook UX21 doesn't get top billing, but then it's got a smaller chassis than the competing units in the test, and therefore less room for battery.

We've only just switched to these new benchmarks, so hope to have both the ZenBook UX31 and MacBook Air results added to these charts soon.


While the performance is very much there for the ZenBook UX21, it falls tragically short at one of the most important factors: human interaction. The touch pad, screen and keyboard will make you want to pass by this one product — no matter how pretty it is. We have no doubt Asus is beavering away right now at the successor — we can only hope it addresses these concerns.

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dang2218 posted a comment   

Win8 drivers improve the touchpad.The screen remains poor at most angles but straight on it is ok .


Ducatisupersport999 posted a comment   

Contrary to the CNET Review (that is usually spot-on) this is the best portable computer I've ever purchased. it is everything I wanted in size, weight and performance and hell it looks great too.

MotorMouth Facebook

"Better Than You'd Think Was Possible"

MotorMouth posted a review   

The Good:Stellar performance, gorgeous to behold, ridiculously small and light

The Bad:Battery life could be better (but is not really that bad)

I bought a UX21 last November from JB Hi-Fi, who did me a ridiculously good deal on a machine that had only been on the market for a week. I bought it because it was tiny, sexy as hell and ridiculously cheap ($1350) for what it can do.

Before I review it, I'll mention that my last laptop was a high-end Vaio SB19GG, effectively the most powerful 13.3" laptop money could buy a year ago, which cost me $2500. It replaced a Dell M4400 mobile workstation that featured QuadroFX graphics that cost me $3600. I'll also mention that I am a graphic artist, working in film and TV, and I also perform electronic music live on stage, so I push my laptop more than anyone else I know. It has to be able to run 3DS Max, After Effects and real-time music applications with 100% reliability and maximum speed.

OK, so how does the UX21 stack up against such expensive, high-spec machines? Basically, it blows them away. Most impressive is the SandForce SSD, which is noticeably faster than the dual SSD RAID in the Vaio. It makes working with PAL Widescreen video (1024x576) almost real-time in After Effects and contributes to making the UX21 feel so capable. The Core i7 CPU is also very impressive and watching the meters on the Turbo-Boost gadget is quite addictive. 2D and 3D render times are at least as good as the Vaio's and real-time music performance, a real test for any CPU, is actually better.

The Achilles heel of many small/cheap laptops has long been their integrated on-board graphics, which have always precluded them for my shopping list. However, Intel's HD3000 is actually more than handy in that department. My standard graphics test is to fire up Autodesk Combustion and see how much interactivity I get from it's OpenGL powered particle system. HD3000 gives me realtime performance - 25 frames-per-second at PAL widescreen resolution while I drag motion paths around in the viewport. It works as well here as it does with Dell's QuadroFX, allowing me to have thousands of particles respond in realtime.

What about the keyboard and trackpad, you ask. Well, most of the time mine is plugged into an HD monitor and a USB hub with keyboard and mouse, but I did take it on a 3 week holiday before Xmas, so I have had to use them a bit. The trackpad is perfectly OK, although I hate all trackpads and almost always use a mouse, and the keyboard just requires you to adjust your typing style a little. The main problem I have with it is the spacebar, which doesn't always respond to the side of my thumb, so I just got in the habit of using my index finger instead. I actually found that it reduced the number of typos I make (and I make a lot), so it was really a good thing, sort of. The other minor annoyance is also another plus - instead of just a few little rubber stoppers to keep the screen separated from the keyboard, the UX21 has a rubber seal running all the way around (like a fridge door in miniature). This can make it hard to open if you've had it in a bag or something, but as long as you have fingernails it is not a big problem. For me, none of it is so bad as to detract from the overall experience, even slightly.

To address a few other issues raised in the main review, I think the screen is a standout feature, easily matching any I've used and better than the Vaio's. I have no issues at all with vertical viewing angles (unlike my HD monitor). The included sleeve is also really nice - with a stiff plastic or cardboard backbone, felt lining and the use of two materials outside. You even get a matching pouch for the ethernet and VGA connectors. Very classy. I've also not had any problems with excessive heat. Yes, I do have to open the lid a little when I am doing CPU-intensive work but the chassis doesn't get any warmer than other laptops I've owned.

Overall, what impresses me most is that I have an 11.6" laptop that cost $1350 that is not only gorgeous and extremely robust but it easily out-performs laptops 4 times the size and 3 times the price. Why anyone would spend a grand on a stupid tablet when they could have a lower power version of this for the same kind of money is completely beyond my comprehension. Its also about $500 cheaper than the equivalent MacBook Air and I have no doubt the UX21 would outperform it, too. The UX21 looks a lot classier, too.


"Deserves a second chance with the new drivers installed"

ZenbookNovice posted a review   

The Good:Speed, size, weight, value

The Bad:Screen (in power save mode)

After hanging around the Macbook Airs a silver-tongued salesman had me considering my phobia of learning a new OS and leaving the store with a saucy new UX21E at 20% less $ than the cheapest Air. Imagine my horror when I read your review...It stayed in its box for a week while I considered returning it unopened. Then I read a recent review on a US equivalent to Cnet and was much more reassured.
The trackpad is well and truly fixed by downloading the latest update from Asus (heavens only knows why this isn't done automatically). As I'm not an Apple user I can only benchmark it against other Windows laptops I've used, and it's a much better pad, with a few cool tricks akin to iPhone style swipes etc.
The keyboard is fine, I read somewhere the keys aren't profiled with a dip: they are. Disclaimer: I'm not a touch typist, the other review said it's not for very soft typists. The keys go into a raised surround, missing the middle of the keys and getting caught on the surround seems to be the main cause of missing letters.
WiFi updates are recommended automatically, and I've been downloading all day with no hassles with the speed and reception fine. All day being several hours, and no you can't cook an egg on it! It's perfectly cool.
The power button is indeed in an odd place - right by the delete button. I've not hit it by accident yet, but at least it doesn't turn off without asking first!
My big surprise (naivety) was that 35GB is swallowed up straight off the bat by the OS and programmes etc. I'll be looking into clearing some of that out. I backed up the OS to a hard drive saving 8GB, important as I only got the 64GB version.
I was also disappointed by the screen until I turned off the power save function when I plugged it in and what an amazing difference. In high performance mode the screen is great, although I don't know how it would compromise the battery life. The viewing angle would still annoy somebody looking over your shoulder...if that's what you want? (yes the "buzzing" feeling on the brushed metal is a bit disconcerting, but you get used to it).
The best thing is the speed of this thing. It's only the Core i3 version and it seems every bit as fast as when I'm plugged into the network on my work desktop. This might not be a very technically accurate test compared to the diagnostics Cnet run, but I think that's the point of my review. As a non-techie person this machine is way better than any laptop I've used before. Whilst it may not be the perfection Cnet are pushing the companies to, it's a major leap forward if compared to full sized, full weight, laptops, which ceased to be laptops when you could no longer tote them about without a backpack!
The laptop is actually a gift for my wife, so I'll update this if she agrees...or makes me take it back and fork out the extra$$!

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User Reviews / Comments  Asus ZenBook UX21

  • dang2218


    "Win8 drivers improve the touchpad.The screen remains poor at most angles but straight on it is ok ."

  • Ducatisupersport999


    "Contrary to the CNET Review (that is usually spot-on) this is the best portable computer I've ever purchased. it is everything I wanted in size, weight and performance and hell it looks great too."

  • MotorMouth



    "I bought a UX21 last November from JB Hi-Fi, who did me a ridiculously good deal on a machine that had only been on the market for a week. I bought it because it was tiny, sexy as hell and ridiculo..."

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