Compaq's Armada M300 sub-notebook has been updated, and now uses a 600MHz Intel Mobile Pentium III processor. Ultra thin, and ultra light, the M300 itself is only 2.7cm high and weighs just 1.4kg.

Users needing a floppy disk or DVD/CD-ROM drive (the standard unit has neither) can buy either dedicated external units or Compaq's Mobile Expansion Unit (MEU), which when docked forms a two-slice, three-spindle system. Even this combined unit is only 5cm high, with a total weight of around 2.5kg.

The standard four-cell battery gives a pitiful life of just over one and a half hours, although a useful charge meter is incorporated into the battery. A longer life battery is available as an option - and it's one we'd recommend. The cylindrical battery pack attaches below and to the rear of the top slice, and can also be used to provide a different keyboard angle if rotated downwards to rest on a flat surface.

The M300 we reviewed had a 12GB hard disk and an 11.3-inch TFT screen driven by a 4MB ATI Rage LT Pro. A V.90 modem/NIC combination Mini-PCI card is installed, freeing up the single Type II PC Card slot for other uses, and there are the usual ports, including line-in/line-out jacks, parallel, serial, video-out and USB ports.

These ports are duplicated on the MEU, with the exception of the modem/LAN ports, plus there are dedicated PS/2 mouse and keyboard ports on this expansion pack. The MEU that came with the M300 reviewed was supplied with a standard floppy drive and a Compaq 24-speed CD-ROM drive.

Although a little slow compared to the other systems here - only the standard 64MB of memory was fitted - this is a well-designed and useable platform. Definitely go for the bigger battery, though.