Asked on his platform X whether he would hire Nvidia’s embattled chief executive, Elon Musk did not hesitate. “That would be an honour,” he wrote, after one user posted, “Elon, please hire Jensen.” The remark came as Jensen Huang’s grip on the chipmaker faced its most serious challenge in years.

Musk had already signalled his sympathy. He endorsed a post by Sequoia Capital partner Shaun Maguire, who praised Huang as one of the finest entrepreneurs of his generation while conceding that the Nvidia boss had blundered badly. Maguire wrote that Huang had done something incredibly dumb and harmful to America, yet doubted there was any malicious intent. He argued that two mistakes did not make a right and that he believed Huang was irreplaceable for America’s AI leadership. Musk replied simply: “I agree.”

The exchange unfolded as Huang’s conduct put one of the defining companies of the artificial intelligence boom under a cloud. According to reports, Nvidia’s board was due to convene on Wednesday to weigh his future, with the chief executive facing new infidelity allegations tied to a woman said to have spied for China.

The board had already launched an independent inquiry after Huang admitted to an affair in an email to staff. Reports linked him to Nvidia’s vice president of health care, Kimberly Powell, the second such claim against him. An earlier alleged affair was said to have involved a Chinese executive, Alice Huang, also known as Huang Le, whom US intelligence agencies reportedly suspect of espionage for Beijing. None of the claims have been independently verified.

Investors reacted sharply. Nvidia shares dropped by as much as 10% in post-market trading in New York on Wednesday and 13% across five days. Should those after-hours losses stick when regular trading reopens, the chipmaker would fall back below $4 trillion in market value.