Sony VAIO VGN-SZ1VP review

Despite all the research ploughed into the pursuit of all-day notebook mobility, we still rarely see more than five hours' life away from the mains. In an attempt to extend that, Sony has come up with the novel idea of fitting two separate graphics processors in order to save power. Not only do you get Intel's standard integrated Graphics Media Accelerator (GMA) 950, but also a discrete nVidia GeForce Go 7400 GPU. The idea is that you can than slip from one to the other as needs dictate - just flip the two-position switch between 'stamina' and 'speed' and reboot.

For any standard 2D desktop application, the GMA 950 chip is fine. The zippy T2500 Core Duo CPU of this flagship model takes the lion's share of the strain, with our application benchmarks scoring 1.09 under the nVidia adaptor, compared to 1.07 when relying on the integrated silicon. You're then left with the Go 7400 lying in wait to give a boost to any 3D tasks, primarily gaming (both cards have various optimisations for movies, but ultimately the difference isn't worth the reboot).

The Go 7400's TurboCache feature utilises up to 128MB of system RAM to increase its power, and its gaming power stems from eight pixel pipelines and three vertex engines. However, it's still a fairly low-end GPU and will struggle with modern games at anything more than basic settings. It barely coped with our standard 3D benchmarks, scoring 22fps in Far Cry only once we'd removed anti-aliasing and anisotropic filtering. Taking the resolution down to 1,024 x 768 and removing effects improved matters, taking the frame rate up to a playable 32fps against a mere 6fps from the GMA 950.

Choosing the integrated graphics will theoretically cut down on power consumption during general use, using negligible amounts of power against the 10W TDP of the Go 7400. In real terms, we saw our light-use battery time rise from four-and-a-half hours to six-and-a-half hours. Putting the SZ1VP through more intensive tests showed the difference just as well; the integrated graphics eked a further half hour from the discrete card's one hour, 32 minutes. These results are some of the longest we've seen and particularly impressive given the weight.

The chassis itself is classic VAIO - sleek, stylish and understated - and that extends to the LED-backlit screen, with its incredibly thin 5mm depth. However, we're not overly concerned about accidental damage, as the flexibility avoids too much strain on the lid should you cram the VAIO into an over-packed bag.

And the 1.7kg weight and 13.3in diagonal panel mean the SZ1VP fits into the might-as-well-take category when travelling. The resolution of 1,280 x 800 is high enough to get some serious work done without being too cramped. It also boasts excellent viewing angles, a bright and even backlight, plus a good technical performance in terms of colour accuracy and movement handling. The keyboard feels light and responsive too, and benefits from an exemplary layout.

With a tastefully integrated 0.37-megapixel webcam, microphone and bundled Bluetooth headset, videoconferencing is an obvious application for the SZ1VP. Security is also high on the list of priorities, with a Trusted Platform Module installed on the motherboard. In conjunction with the MySafe software, security can be enforced at all levels, from single files up to whole directories, and the swipe-style fingerprint will double up as a password safe for website logins. More reassurance comes in the form of hard disk shock protection - a first for a VAIO - with an accelerometer parking the read/write heads immediately upon detection of sudden movement.