LOS ANGELES, Nov. 12 -- For nearly two decades, Kimberly Powell has been the person Nvidia sends out to explain what its chips can do for medicine.

This week, she became a name nobody at the company wanted to see in the headlines.

Powell, 48, Nvidia's vice president of healthcare, was named by the New York Times (NYT) yesterday as the senior executive with whom chief executive Jensen Huang allegedly had an extramarital relationship, a claim neither has confirmed.

The NYT, citing five people who worked at the company, said Powell reported to Huang.

Her sudden prominence is the latest twist in a scandal that has engulfed one of the world's most valuable technology companies in less than a week.

An engineer first

Powell's route to Sili...