Acer Inc., Toshiba Corp. and Asustek Computer Inc. will unveil tablets running Microsoft’s windows 8 operating system next week. People with knowledge of the matter said, challenging the dominance of Apple Inc.’s iPad.

Acer will display a tablet based on Microsoft’s new software at the Computex show in Taipei, while Toshiba will show a tablet and a notebook-type device, said the people, who asked not to be identified because the plans haven’t been made public. Asustek will present tablets with detachable keyboards similar to its current Transformer model.

The annual Computex show provides a forum for the computer industry to tout its wares before the typical increase in second-half demand. Computer makers allied with Microsoft will use this year’s event to highlight a long-awaited response to the iPad and machines that run Google Inc.’s Android operating system, which together have 91 percent of the tablet market.

Windows 8 also will be the first version of the software that will work on processors using ARM Holdings Plc technology, a type of chip made by Qualcomm Inc., Texas Instruments Inc. and Nvidia Corp. that dominates the phone industry. ARM-based chips, manufactured by Samsung Electronics Co., power the iPad.

The use of ARM-based chips marks a snub for Intel Corp., which along with Advanced Micro Devices Inc. has been the exclusive provider of chips for Windows machines. Intel, which has more than 80 percent of the PC-chip market, hasn’t been able to parlay that dominance into market share in phones or tablets.

Asustek will demonstrate tablets based on an Nvidia ARM- based chip called Tegra and another powered by an Intel chip, the people said. The Tegra-based device, which is similar to the one that will go on sale, will be displayed publicly, setting up an opportunity for direct comparisons between a Windows computer running on ARM and one using Intel technology.