Acer has updated their 2009 Timeline portable laptop range by adding even more battery life as well as a large letter to the end of the product.

The TimelineX series comes with the Intel Core i family of processors for more power, rather than the ultra-low voltage chips of the previous models, and the added efficiency comes from an improved HDD - with lower noise and running temperature - an improved LED backlit screen and an assortment of power saving settings. The result is a running time of up to 12 hours (provided you opt for the 9-cell battery, 8 hours if not).

"We wanted to create a series of laptops that you could treat like mobile phones", said Acer UK mobile PC product manager Martin Mobrini. "The idea is that you charge it up over night and it lasts you the whole of the rest of the day".

The TimelineX laptops will come in 13.3-, 14- and 15.6-inch sizes as before with an 11.6-inch version to come later. Each comes with a 720p screen, up to 8GB of DDR3 memory (3GB as standard) and storage between 250-640GB.

The chassis are brushed aluminium - black on the outside, silver on the inner - they're all less than an inch thick and weigh 1.8, 2.2 and 2.4kg respectively.

On the entertainment side, these machines have Dolby Home Theatre v3 to approximate a 5.1 set up and the larger two sizes have dedicated ATI GPUs, which can be specced up to the 1GB Radeon HD5000.

The Acer TimelineX laptops will be out in May with the basic configurations starting at £599.