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Asus’ U-series laptops have impressed us over the last couple of years with their long battery life, despite the use of normal Intel Core processors, rather than the low-voltage variety used by most other ultra-portables. The new U31JG follows this trend: despite its 2.67GHz Core i5-480M processor and a dedicated graphics card, it lasted for over ten hours in our light usage test.
This is largely thanks to Nvidia’s Optimus technology, which switches between the processor’s integrated graphics chip and the GeForce GT 415M depending on whether you need performance or battery life. It’s not that fast – a score of 17fps in Call of Duty 4 means you’ll have to turn off most of the graphical effects in a modern 3D game to get playable frame rates – but it supports Nvidia’s CUDA which helps speed up certain operations in programs such as Photoshop. It will also easily decode HD video content.
You might want to output HD content to a larger monitor via the HDMI output, or pipe both audio and video to an AV amplifier. Movie soundtracks would certainly benefit as the U31JG’s internal speakers aren’t particularly inspiring, with a very compressed sound and no bass. If your sound system doesn’t have an HDMI input, you can also output audio via the headphone socket, which doubles as an S/PDIF output.
The screen more than makes up for any slight shortcomings with audio. We found that the 13.3in screen had a bright, even backlight and vibrant colours. This is partly due to the glossy finish on the screen, but the downside is that this can also reflect overhead lighting. Vertical viewing angles are also very tight, so you’ll have to adjust the screen’s tilt carefully to get the best picture. Once you get it right, however, it has good contrast and natural colours. Its resolution of 1,366×768 gives plenty of room for HD movies or the Windows desktop.
Previous U-series models were made entirely of black plastic, but the U31JG adds a bit of variety with a grey wrist rest – otherwise, the brushed-metal-effect lid and glossy black screen bezel match previous models. Construction seems sound, with little flex in the lid, but sadly there’s quite a bounce in the keyboard panel. Thankfully, the keys’ action is light, with a crisp bite in the keystroke that provides enough feedback to compensate for this flex.
Below is a medium-sized touchpad that’s responsive and supports multi-touch gestures. It has a single see-saw button that has a very shallow action and a large central dead area, but it’s usable. Typical of an ultra-portable, the U31JG has no optical drive, but instead has a fairly standard collection of ports – three USB ports, VGA and HDMI video outputs, an Ethernet port and a memory card reader.
The U31JG’s Core i5-480M managed an overall score of 56 in our new benchmarks, putting it behind only the new Apple MacBook Pro in terms of raw performance. A score of 85 in the single-threaded image-editing test shows off the Core i5’s Turbo Boost, which can push the processor’s clock speed up to 2.9GHz, and with two physical cores, expanded to four cores through Intel’s Hyper-Threading technology, it’s no slouch when you’re running multiple programs or using multi-threaded applications such as video-encoding.
With decent performance as well as good battery life, a vibrant screen and a sensible selection of ports and other features, the U31JG ticks all the right boxes. It may not be the most stylish or exciting design, but at just over £600 it’s great value, especially when you consider the two year warranty, so it wins our Best Buy award.
