''So, it has come as hardly a surprise for us to find that some of the best-performing notebooks around are based on this new DX4 chip.

''What's even more attractive for notebook users is that this enhanced performance does not adversely affect battery life.'' The DX4 processor, that some of the leading notebook vendors have used in their products, works at 75 megahertz. Later this year, a 100-MHz version will be released.

The DX4 is attractive to designers because they need to make only minor alterations, to systems designed for earlier 486 chips, to use the latest processor and tap its additional power.

The DX4 has 16 kilobytes of on-chip caches, twice as many as the DX2 microprocessor. It also needs less power, 3.3 volts, for use with long battery life notebooks and for energy-efficient desktops.

Some of the big companies that feature the fast DX4 notebooks are Compaq, Toshiba, Acer, AST, VTech and NEC.

Compaq has the chip in its latest generation of LTE Elite notebooks.

This notebook range follows Compaq's success with the LTE Lite family of notebooks.

Simon Hong, marketing manager of Compaq Computer Hong Kong, said: ''We started shipping from last month LTE Elite notebooks with the DX4 processors working at 75 MHz, with plans to feature the 100-MHz processor when it becomes available later this year.

''It has been particularly popular with multinational companies, financial firms, and telecommunications companies. They enjoy the extra processing capability and features of the Elite notebooks with the DX4 processors. The response from our clients has been extremely good.'' The Elite notebooks with the DX4 come with at least eight MB of RAM and hard disks of either 340 MB or 510 MB, and eight MB of memory that can be upgraded to 24 MB. It has an active matrix display and users can also get three desktop expansions by using the Compaq SmartStations.

''These SmartStations offer plug-and-play features, including a motorised VCR-style docking system, built-in Ethernet and broad expandability,'' Mr Hong said.

''These notebooks come pre-installed with MS-DOS 6, Windows 3.1, Microsoft Video for Windows 1.1 Runtime and Compaq TabWorks,'' Mr Hong said.

''Among the other features are a hugely popular integrated A/C adapter, which means that it does away with the heavy, cumbersome external A/C adapter, and only weighs 3.06 kilograms. There are two models that feature a DX4 on-board with a retail price tag of between US$6,469 and US$7,023.'' Toshiba, another popular brand in Hong Kong, has also incorporated the DX4 chip in its new T4800CT model.

Francis Fong, sales manager in the computer division of Toshiba's local agent, Chevalier (OA), said: ''Toshiba has managed to avoid the drawbacks of some other notebook models in the market in its new T4800CT model, which offers the no-compromise, lightning-fast 75-MHz processor from Intel.

''With an integrated cache and co-processor, local bus, eight-MB standard memory and a graphics accelerator, the T4800CT can match the performance of a desktop.

''There are two versions, one featuring a 320-MB hard disk and another with a 500-MB hard disk, retailing at HK$53,000 and $56,300 respectively.'' The notebook can be expanded easily through two PCMCIA slots and a DeskStation IV port. The DX4's power allows the notebook to cope with the presentation needs of most executives.

It has built-in audio with a Microsoft Windows-compatible sound system.

The DX4 chip has been an instant hit with notebook vendors and users.

As Compaq's Mr Hong said: ''We are now planning to offer notebook users even more power and features with a faster DX4/100-MHz processor.

''Users can expect to get their hands on our notebooks featuring this advanced chip by the end of the year.''