The HP Compaq range is aimed at the business user and with the nx9420, it's the office worker looking for a desktop alternative that is being addressed. The build quality of the chassis is the first thing you'll notice, with plenty of protection behind the lid and a solid feel to the main body. The 17-inch Super-TFT is held firmly in place and while it's not the brightest screen we've seen, the 1,680 x 2,050 pixel (WSXGA ) panel is large enough to get two documents side by side for easy comparison.

Weighing in at 3.4kg, there isn't really a weight penalty in opting for such a machine with such a large screen, but if you carry it around you'll soon start to feel the weight. That said, in its favour is a battery life in excess of four hours, so you'll easily be able to get a full morning's work completed while out and about.

When it comes to getting the job done, there is more than enough power to be found here. Using Intel's Core 2 Duo T7400 (2.16GHz) processor, you'll find this machine really delivers. The 1024MB of DDR2 memory means the system won't slow when running multiple applications.

Graphics rely on the ATi Mobility Radeon X1600, which is shortly to be replaced by the X1700, offering 10 per cent more performance. The battery occupies the back of the case, so you won't find any ports here, which has forced HP to move them to the sides of the machine. On the right-hand side you'll find a DVD rewriter, Gigabit Ethernet and two USB 2.0 ports, as well as headphone and microphone jacks.

There are also two USB 2.0 ports on the lefthand side, along with S-video and VGA-out ports and a SecureCard slot, which means you can add an extra layer of security should your company support it.

Fine keyboard

It's not only the case that is well built, as the keyboard is sturdy and has a firm typing action. With such a large chassis design, there is room for a numeric keypad. The board is in a small recess, which stops the keys rubbing against the screen in transit.

It may be designed for the office user, but you'll find a number of features the home user will appreciate too. For instance, the screen has a glossy coating, which is ideal for watching DVDs and the addition of a multi-format card reader built into the front of the chassis means you can swiftly share data from a memory card.

This is one of the most powerful machines we've tested to date and the results are stunning. HP has produced a great machine in the nx9420 that will appeal to large and small business users alike.