The Portege R600 has long been one of our favourite ultraportables and it has now been upgraded with the Portégé R700 – the lightest Intel Core-powered laptop we've seen at 1.1kg.

Toshiba claims up to nine hours of battery power will be on offer, but since our review sample was a pre-production unit, we were unable to confirm this.

Despite its tiny form factor, the review sample we saw featured a high-powered Intel Core i7 620M processor and 4096MB of DDR3 memory. Core i3 and i5 models are also planned for release and even at this pre-production stage this is one of the most powerful ultraportables we've seen.

During preliminary testing, we found the laptop extremely fast to use, running standard office applications and more demanding programs with ease.

The use of an integrated Intel GMA HD graphics card means even basic multimedia tasks such as photo or video editing are also possible.

Toshiba and Intel have developed what they call Airflow Cooling Technology. This places the core components near the chassis' edge so that a fan can continually draw cool air into the chassis to be blown over the components to keep them cool.

The system works well in allowing such powerful components to be used inside such a small laptop, but we did notice the left side of the chassis gets quite hot during intensive use.

Resilient design

As well as being thin and light, the chassis is incredibly tough. Only the lid feels flimsy, but is in fact designed to flex under pressure, reducing the risk of cracking.

The 13.3-inch screen uses transflective LED screen technology for optimum visibility indoors and out, and the panel provides great colour and contrast.

Usability is less impressive, although this could be a result of our pre-production test machine, with the isolated-style keyboard proving one of the spongiest we've used.

To keep the chassis as light as possible, a 128GB Solid State Drive (SSD) has been used rather than a standard 2.5-inch hard drive. While SSDs are less prone to data loss caused by knocks and bumps and also provide very fast access to your data, the limited storage space is an unfortunate trade-off.

More pleasing is the fact that Toshiba has managed to squeeze a DVD rewriter into such a small laptop, for read/write access to CDs and DVDs.

Connectivity is also top-notch, courtesy of 802.11n Wi-Fi, Gigabit Ethernet. There's also a 3G module for wireless broadband access.

Even at this pre-production stage, we're very impressed by the Portege R700. While there are a few minor niggles, we're confident they will all be resolved for mass-production and this is sure to be a big winner for Toshiba.

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