This is the third notebook we’ve seen from Asus’ Eee range, but in many respects it’s version two of the Eee.

The 900, released only a few months ago, simply added a larger screen and Windows XP to the original design, but the 901 has a new case, better networking and, crucially, a new processor inside.

The Eee’s system tool coyly describes its CPU as an “Intel Mobile Processor” but we understand that it’s Intel’s brand-new Atom N270, running at 1.6GHz – the same as used in Acer’s Aspire One.

This new chip is paired with 1GB of Ram and a large SSD for storage: 20GB for this Linux version or 12GB if you choose Windows XP.

The Atom runs at a significantly higher speed than the Celeron chip used in older Eee models and the 901 certainly feels responsive when clicking around the Linux operating system. There’s a cooling fan inside the case, but this is very quiet.

Perhaps more importantly, the combination of the Atom processor and a new and improved 6,600mAh battery pack gives the 901 an outstanding lifespan when away from mains power. With wireless networking disabled but the screen on, it ran for nearly six and a half hours in our test.

One thing about the Eee 901 remains depressingly similar to previous models: the keyboard. Although barely an inch narrower than that of the Aspire One, it’s too small to type on comfortably, so writing anything longer than an email soon becomes a chore and even web addresses are easy to mistype. On the other hand, the touchpad is superb.

Although the case looks different from older models, with rounder corners and the Asus brand name relegated to the bottom plate, the sockets around its edges are nothing new: there’s a VGA output, three USB sockets, headphone and microphone jacks and an SD memory card slot for expansion.

Above the screen there’s a 1.3-megapixel webcam, though, and there are two microphones below the screen. New additions inside the case include Bluetooth and a faster 802.11n-compatible wireless network adapter.

The 8.9in 1,024x600 display is fine for surfing the web or working on documents and, although it has the same resolution as that on Acer’s Aspire One, the neater font smoothing used by the Eee makes text look clearer and sharper.

The menu-based Linux operating system also shows the benefits of Asus’ experience with the earlier Eee 701. It uses the same tab system, with each tab offering a different choice of large, clear program links.

The taskbar across the bottom of the screen includes useful information about USB devices and performance settings as well as the usual power and network indicators. Staroffice, Firefox, Thunderbird and the instant messaging client Pidgin are installed as standard. One new and unusual bonus is the Internet Storage icon – click this and you can connect to the 20GB of online storage that’s provided free with each Eee 901.

All things considered, there’s no doubt that the 901 is the best Eee notebook yet. It takes the great screen from the Eee 900 and the 701’s clever Linux operating system, and adds a superb battery and better networking. On the other hand, it faces strong competition from the likes of Acer’s Aspire One, its keyboard is as frustrating as ever and at £319 it’s fairly expensive.

It is without doubt a great second computer if you have another PC to type on, but work and home users should consider the cheaper Aspire One – with an extra battery if needed – instead.