“The era of a perfect Internet computer for $99 is coming this year,” said Jen-Hsun Huang, the chief executive of Nvidia, a maker of PC graphics chips that is trying to adapt to the new technological order. “The primary computer that we know of today is the basic PC, and it’s dying to be reinvented.”

An unexpected group of companies has emerged to help drive this transformation  firms like Qualcomm, Freescale Semiconductor and Samsung Electronics, which make cheap, power-saving chips used in cellphones and are now applying that expertise to PCs.

As in any revolution, the current rulers of the kingdom  Intel and Microsoft, which make the chips and software that run most PCs  face an unprecedented challenge to their dominance. Microsoft is particularly vulnerable, since many of the new netbooks use Linux software instead of Windows.

“A broad shift in the consumer market toward low-cost PCs would clearly put pressure on the revenues of nearly every player in the value chain, from component suppliers to retailers,” wrote A. M. Sacconaghi, a securities analyst with Sanford C. Bernstein & Company, in a report last month. “However, we believe the impact would be especially negative for Intel and Microsoft, who today enjoy near monopoly positions in their respective markets.”

So far, netbooks have appealed to a relatively small audience. Some of the devices feel more like toys or overgrown phones than full-featured computers. Still, they are the big success story in the PC industry, with sales predicted to double this year, even as overall PC sales fall 12 percent, according to the research firm Gartner. By the end of 2009, netbooks could account for close to 10 percent of the PC market, an astonishing rise in a short span.