Asus U31JG review

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 1,366x768 gives plenty of room for HD movies or the Windows desktop.