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Cinebench 10: 7297
3D Mark '06: 4096
Battery Eater: 189mins
The Asus Zenbook UX21's Intel Core i5 2467M processor scored well in our lab tests, notching up 7297 in Cinebench, making it easily as fast as chips found on most mid-range laptops. It's fully capable of multitasking standard tasks such as web browsing, streaming online video, picture editing and playing HD video.
When you consider the waif-like form of the Asus Zenbook UX21, it's incredible that it can compete with bulky portable laptops.
In terms of graphics performance, the numbers that denote the quality of games, video rendering and programs such as Photoshop show that the Asus Zenbook UX21 doesn't stack up so well.
There's no dedicated graphics card here, so the processor handles the 3D effects instead. There's enough power to watch video and make simple edits to video, but hardcore graphics programs and even mid-range games would test the system beyond its limits.
Battery life is also good, and we achieved 189 minutes using our lab software, which involves simulating document writing while looping HD video in the background. In real terms, you can watch a full HD movie before reaching for the charger, or expect around five hours of web surfing and writing before your laptop dies.
If you're away from the mains all day, then you might not consider five hours to be enough, but you'd have to look to the Sony Z Series to get anywhere near the same power and portability as the Asus Zenbook UX21, and that would mean a huge jump in weight and price. The Sony Z Series and its external power pack cost in excess of £2,600.
One of the most noticeable attributes of the Asus Zenbook UX21 is the speed in which it resumes from sleep. Using innovations from Intel, the Zenbook resumes instantly, without the hangs and loading periods that have historically plagued Windows machines. This is the most tangible benefit, and brings the fight to the host of tablets on the market.
The screen itself is excellent, and it's one of the best panels we've seen in a small form notebook. With the resolution equivalent to that of a larger 15-inch laptop, you can enjoy text documents and web pages properly, not like on a netbook, where the lower number of pixels means that web pages look zoomed it, meaning you have to scroll every few lines.
If you're a regular traveller, and you like watching movies, then the Asus Zenbook UX21 is perfect, and has enough power to play back high-definition video. The extra two inches over a tablet makes all the difference too, and this means it's a fantastic machine for those who mix work and play while on the move.