• Editors' rating
    7.5 Very good


  • Slim and light
  • bright, clear TFT screen
  • good battery life.


  • If you need legacy ports, you'll need a third-party port expander
  • the standard 64MB of RAM will not be sufficient for many users.

Last year, Sony added the SR series to its range of sub-2kg notebooks, filling a gap between the minuscule 1kg C1 and slimline 1.7kg Z600 ranges. Weighing in at just 1.36kg, the new SR21K, which succeeds the SR11K, packs a workmanlike specification into a footprint measuring 25.9cm wide by 20.9cm deep, while the unit's height (3.2cm) makes it one of the slimmest notebooks around. Designed for the mobile professional who's prepared to make a few sacrifices for the sake of portability, the SR21K is an attractive offering at £1,446 (ex. VAT).

The design of the SR series is based around what Sony calls 'zones': the dark purple PC Zone comprises the 10.4in. XGA-resolution TFT display and the 84-key keyboard, while the silver-grey Entertainment Zone houses the stereo speakers, Memory Stick slot, Jog Dial navigation device and touchpad. Despite the fancy naming, the SR21K's design remains quirky, resembling nothing so much as a VAIO C1 with an add-on unit stuck on the front. It's certainly different, but not unattractive.

The SR21K is built around a 650MHz Intel Mobile Pentium III processor, whose SpeedStep technology causes it to run at 500MHz when under battery power (unless you override this default setting). If all you want to do is run mainstream applications, a 650MHz CPU should be plenty powerful enough, but the SR21K is disappointing in only providing 64MB of RAM as standard -- especially as it ships with Windows 2000 Professional installed. This dearth of memory is reflected in the SR1K's benchmarks, a Business Winstone 2001 score of 16.7 looking distinctly sluggish in today's market. The 4,200rpm 10GB IBM hard disk performs reasonably well, and is capacious enough to accommodate Windows 2000 and a good bundle of software with some room to spare.

If the SR21K's performance is disappointing, there's better news on the battery life front -- a traditional weakness with Sony notebooks. Even with power management disabled and the CPU running at the full 650MHz, BatteryMark 4.0 reported just over three hours' life from the 3,600mAh Li-ion battery. With the CPU clocked down to 500MHz, we got a very respectable 3 hours 52 minutes' life from the unit. Sony's PowerPanel application allows you to fine-tune power management settings, and should allow you to achieve around four hours' life without too much trouble.

Given its diminutive dimensions and low weight, you must expect some absentees in the I/O and expansion departments, and you'll look in vain for serial, parallel, PS/2 infrared and network ports - there's not even an optional port replicator. There's a single USB port, a proprietary port for a VGA adapter cable, an i.LINK (IEEE 1394) port, and RJ-11 port for the internal V.90 modem plus a pair of audio ports. The external 16X CD-ROM drive attaches via the single Type II PC Card slot, and there's also a Memory Stick slot, which will be of most use to those who embrace Sony's all-embracing 'Go Create' vision.

The SR21K is an interesting ultraportable notebook that mobile professionals should certainly consider, especially if they want something out of the ordinary. However, many potential users will want to specify extra RAM, which will obviously push up the cost.