Mr. Ruiz recently published a book about his efforts to sue Intel for monopolistic practices, which he said were the natural result of its paranoia. Intel paid A.M.D. $1.25 billion to settle the case after he left the company, but Intel has consistently denied it engaged in monopolistic practices.

The idea that Intel put the squeeze on its customers has been around Silicon Valley for years, but has never been proved. With Intel controlling 80 percent of the PC market at times, and PC makers facing low profit margins, any supply interruption from Intel could be disastrous.

But any such threat may be less significant in the future.

At a meeting last week in New York, Hewlett-Packard, a longtime buyer of Intel’s server chips, showed off a server built for the cloud that ran on a low-power Intel chip, called Atom. But sharing the limelight were representatives of four other companies that will sell chips to H.P. for other versions of the machine.

Even Microsoft has been moving away from its longtime partner as it tries to adapt to the new, post-PC world. Last year, Microsoft built its own tablet, with versions carrying chips from Intel or Nvidia, another Intel rival. Its new Xbox game console will use chips made by A.M.D. And the company’s mobile version of Windows 8 is designed for smartphones that run on chips from Qualcomm.

Microsoft declined to comment on its relationship with Intel.

Intel figures its survival depends on preserving its leading position in cutting-edge semiconductors, despite the high design and manufacturing costs. Future generations of the Atom chip, which can also be used in tablets, phones and other devices, are expected to offer better performance, including a longer battery life. So will the next version of its chip for PCs, called Haswell, which will be used in products in the second half of 2013.

“I contest that this market is in decline,” said Mark Bohr, a senior fellow in Intel’s technology and manufacturing group. “Today’s marketplace is a lot broader than 10 years ago. We have got to build for small tablets and big mainframe computers, build more flavors of each chip, and cover more bases.”

Mr. Otellini has been criticized for responding slowly to the mobile challenge and cloud-based computing. His efforts have been modest, geared to learning how to listen and respond better to customers.