New Delhi, Aug. 25 -- Amazon.com Inc.'s Andy Jassy has begun making an audacious boast during conference calls this year. Though his company remains a top Nvidia Corp. customer, it's also one of the world's largest makers of data center chips in its own right.

If Amazon's semiconductor operation were a standalone business, it would generate annual revenue of more than $25 billion, the chief executive officer told analysts in July. And the sales are growing by a percentage in the triple digits.

"We're quite excited about what's happening in our chips business," Jassy said.

The swagger underscores how much the semiconductor landscape is changing - and how fast. Though Nvidia remains the dominant maker of data center processors, particula...