Microsoft's much-anticipated Windows 8 operating system is set to take pride of place as tens of thousands of people head to Asia's leading IT fair opening in Taiwan on Tuesday.

The five-day Computex, an annual tech extravaganza in Taipei now in its 32nd year, will provide one of the most comprehensive glimpses yet of the next version of the world's dominant software.

"It's only a few months before the official release of Microsoft's Windows 8 software," said Chang Li, deputy secretary general of the Taipei Computer Association, which co-sponsors Computex.

"So this year's Computex will offer a great occasion to have a look at some of the hardware applications from Taiwan companies."

Windows 8 is touted as Microsoft's long-awaited riposte to the rise of Apple and mobile devices powered by Google's Android operating system. There is no official release date but reports have predicted an October launch.

Microsoft chief executive Steve Ballmer says that Windows 8 will support a wider range of devices including touch- and stylus-based smartphones and tablet PCs, as well as desktops and laptops.

Computex will reflect this with dozens of exhibitors displaying notebooks and tablets running Windows 8, according to organisers.

South Korea's Samsung along with Taiwanese computer makers Acer and Asus will reportedly launch new tablets and notebooks running on the new Microsoft platform.

"The theme of this year's Computex is clear. Visitors can expect a broad range of products related to Windows 8," said Joanne Chien, a senior analyst at a research centre attached to Taipei-based trade publication DigiTimes.

The latest bout of global economic jitters have not affected the trade show with more than 1,800 exhibitors registering 5,400 booths, up two percent from a year ago.

The organisers estimate that the IT fair will draw 36,000 foreign buyers who may place bulk orders worth up to $28 billion.

Computer makers hope that fresh momentum will come from the so-called "ultrabook", a higher-end product that aims to be smaller and lighter than traditional notebooks without reducing performance or battery life.

Ultrabooks made their debut at Computex 2011, but the relatively high price -- around $1,000 apiece -- has hampered the sector's growth.

"If the prices go down a bit, ultrabook is likely to attract lots of users," said David Liu, also from the Taipei Computer Association.

And there is still room for the humble laptop even as tablets take off, experts at the association said, because users still need a portable workhorse in addition to an entertainment device such as the iPad.

Analysts predicted that ultrabook sales will pick up during the Christmas season, aided by the release of Windows 8 and the advent of "cloud computing", which requires smaller hard drives as users store more of their data online.

Apple, a pioneer of the cloud approach, does not take part in trade fairs like Computex or the Consumer Electronics Show in Las Vegas, preferring to organise its own high-octane events to showcase new products.

In contrast, Samsung is pulling out the stops at Computex with its IT products arrayed over some 30 booths.

In line with China's new economic might, IT companies from the mainland such as telecoms equipment maker Huawei will play a bigger role at Computex than ever before.

A total of 312 Chinese exhibitors will use 617 booths to showcase their products, compared with 252 firms taking 527 booths a year ago, according to the organisers.

"It's not clear how many orders they may get from the show, but at least they can use the platform to boost their exposure to possible clients," Chien said.