The first time PC Authority got to take a look at a Twinhead notebook system (the Slimnote VX, Labs tested issue 20, p59) was back in July's test of budget notebook computers. The Slimnote VX, which came with a Pentium II/300 CPU proved to be one of the fastest machines under $4,000. This new notebook from Twinhead, the PowerSlim 600, picks up where the Slimnote VX left off. Once again, Twinhead has opted to go for a slimline form factor with the PowerSlim 600 rather than go for the powerhouse desktop replacement market typified by such machines as IBM's ThinkPad 390X (reviewed p91) or Dell's Inspiron 7500 (reviewed issue 25, p87).

The unit itself comes in at just over 2kg and is only 33mm thick making it a comfortable size and weight for taking it out on the road. The case of the system features a metallic exterior casing which gives it a reasonable look and feel although it isn't as stylish as the magnesium alloy cases of some notebooks. Twinhead has gone to great lengths to ensure that even a system this slim is still quite easy to upgrade and customise. The 6.4Gb hard drive can be easily accessed via a panel that can be opened by removing two screws. Similarly, the spare RAM slot and BIOS chip are situated behind two separate panels that can be taken out with a single screw removal each.

This ability to quickly upgrade components is complemented by also being able to swap in either the CD-ROM drive or floppy drive to sit internally within the system. The floppy drive comes in an external module which plugs into the machine via a proprietary slot, however, the floppy can be removed from the module and inserted into the same bay as the CD-ROM drive. This can be especially useful if you need more battery power for a long trip and don't need the CD-ROM drive which tends to drain power more quickly. Twinhead has even integrated the microphone and headphone ports into the front of the system making them easier to access and avoiding the inevitable cable tangle at the back of the machine.

Because of the PowerSlim 600's relatively small size, the machine features a 12.1in TFT LCD display that can only natively support an 800 x 600 resolution. Fortunately, the Trident Cyber9525DVD graphics chip enables a virtual desktop of up to 1,280 x 1,024 although only in 256 colours. The 2.5Mb of VRAM on the graphics chip was not enough to run our 3D Mark tests in our usual 800 x 600 resolution and only barely managed to complete the tests in 640 x 480 mode. Ultimately, as this machine is not designed for gamers, this is not really much of a problem since the chip is more than adequate for mobile professionals using 2D applications.

One unfortunate consequence of having such a compact notebook is the keyboard and the lack of hand rest space. While I don't consider my hands to be tiny, they are far from being the ham-fisted tools of a heavy-weight boxer. I found it a little constraining to type at the PowerSlim 600 for any period of time. This was compounded by the fact that Twinhead has attempted to integrate as many keys and features into the keyboard as is possible. As a result, one shift key on the right-hand side is smaller and sits next to the arrow keys which can cause problems during long typing sessions.

The performance of the PowerSlim 600 in our applications-based benchmarks were quite fast for a notebook computer although it was not quite at the level of desktop replacement systems such as the ThinkPad 390X and Inspiron 7500. But considering that the PowerSlim 600 is less than half the weight of these notebooks, this isn't all that surprising. A word of warning: if you plan on using this notebook for long periods of time, ensure that it does not sit directly on your lap. I had the system sitting on a desk and, after a couple of hours, I could feel the heat radiating through the bottom of the desk from the PowerSlim 600.

The Twinhead PowerSlim 600 is an excellent choice for the user who needs a light notebook with very reasonable performance.