An Asustek Computer Inc tablet PC on display during a news conference on Monday ahead of Computex Taipei 2011 in Taipei, Taiwan. [Photo/Agencies]

TAIPEI, Taiwan - Attempts by Google Inc and Microsoft Corp to loosen Apple Inc's grip on the booming tablet PC market will be put to the test this week as PC makers unveil new models at the Computex trade show in Taipei.

Investors and analysts will be looking to see if Google's Android operating system can match the popularity of Apple's iPad, while Microsoft may preview its next Windows platform for tablets a year after Apple's first offering hit store shelves.

"Investors want to know which tablet is better, which has the best price-performance, and when the non-iPad camp is going to get going," said Angela Hsiang, an analyst at KGI Securities Co in Taipei. "Previously, people couldn't actually see the products. At Computex, we'll be able to touch and use them."

Acer Inc and Asustek Computer Inc, which upended the computer market when they showed low-cost netbooks at Computex in 2007 and 2008, will demonstrate new tablets featuring Google's Android this week. The operator of the world's most popular search engine and Microsoft will both send executives to the event to meet reporters and update companies on their plans.

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Intel Corp, the world's largest chipmaker, and ARM Holdings PLC, whose chip designs are used by Qualcomm Inc and Nvidia Corp to run tablets, will also try to convince manufacturers that their products are the best as the desktop and notebook markets slow.

Tablet shipments

Global shipments of tablets will climb to 215 million units in 2015 from 17 million last year, according to a May 26 report by Toni Sacconaghi, a New York-based analyst at Sanford C. Bernstein & Co.

Fifteen percent of all tablets will cannibalize the sale of consumer PCs, reducing computer sales growth by 2 percent annually between 2010 and 2015, Sacconaghi wrote.

Competition from new entrants will cut Apple's share of the tablet market to 50 percent next year, iSuppli Corp said on April 21, from almost 100 percent when the company began selling the iPad in June.

Microsoft will preview its operating system designed for tablets this week, using hardware with ARM-based chips, three people with knowledge of the plans said this month.

Microsoft's OS

Machines using Microsoft's new operating system will be released next year, Chief Executive Officer Steve Ballmer said this month, referring to it as Windows 8. Microsoft later retracted the comments, saying they were a misstatement.

Google's early lead in the non-iPad tablet market and strong mobile-phone position has helped it expand its applications store. That success is offset by the company's relative lack of experience in software development, said Helen Chiang, an analyst at IDC Corp in Taipei.

"Most vendors still worry about quality and stability," Chiang said. "At this moment, they choose Google because its cost is lower as the operating system is free, while Windows adds to the price."

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