SAN FRANCISCO (AP) -- Another wave of laptop computers running on Google's Chrome operating system will be hitting stores this summer in the latest challenge to Microsoft's dominant Windows franchise.
The latest line of Chromebooks unveiled Tuesday run on a new generation of faster Intel microprocessors that don't devour as much battery power. The machines will be shipped by major personal computer makers such as Lenovo Group, Acer, Dell, ASUS and Toshiba. They will sell for $300 to $400.
The widening selection of Chromebooks reflects the building momentum for Google Inc.'s attempt to create a compelling alternative to Windows-powered machines and Apple Inc.'s Mac computers.
Intel Corp. and all the PC makers embracing Chromebooks also are longtime Microsoft Corp. partners that helped make Windows so influential and lucrative during the past two decades.
But most of Microsoft's longtime allies have been exploring new avenues amid a two-year decline in PC sales that has been driven by the growing popularity of smartphones and tablets. The technological shift has triggered the slump in PC sales, raising questions about Windows' staying power over the next decade.
Microsoft also alienated some PC makers by releasing its own tablet, Surface, that runs on Windows. Although Surface still hasn't become a hot item, Microsoft's move into the tablet market demonstrated the software makers' willingness to compete against its PC partners.
Intel, perhaps Microsoft's most important partner, has been aggressively expanding beyond Windows. Besides branching into smartphones and wearable technology, Intel also now makes chips for 20 different Chromebook designs, up from just four designs last September.
"We will embrace multiple operating systems," Navin Shenoy, an Intel vice president, said Tuesday.
Meanwhile, Google has been gradually trying to overcome early perceptions that Chromebooks are an inferior breed of PCs because they aren't equipped with a hard drive to store data. In most instances, the Chromebooks require an Internet connection to get to information and applications stored in large data centers run by Google or other technology providers.
Since the first Chromebook came out in 2010, the machines have been upgraded with progressively faster chips, longer-lasting batteries and more online services to accommodate for the lack of a hard drive.
Google also has developed ways for Chromebook users to get work done and entertain themselves even when they are without Internet access. As part of Tuesday's announcement, Google said that the ability to watch movies and TV shows while offline will be included in a free update to the Chrome operating system that will available within the next few weeks.
Despite the broadening support for the product, Chromebooks still account for only a small fraction of PC shipments. About 2.5 million Chromebooks were sold last year, or less than 1 percent of the worldwide PC market, according to the research firm International Data Corp. More than 80 percent of the PCs sold last year ran on Windows.
Chromebooks so far have gained the most traction in classrooms, where the machines' low cost and free software support has won over teachers and school administrators. Google says Chromebooks are now used at about 10,000 schools, doubling from 5,000 last September.