Jensen Huang has resigned as chief executive of Nvidia after reports of extramarital affairs with an alleged Chinese spy and a company employee.

He will be replaced on an interim basis by Nvidia’s chief financial officer, Colette Kress, until a full-time successor is named.

Shares in the chipmaker plunged by 13% when Wall Street opened, after Huang’s departure was announced. After a partial rebound, they were down 7% in morning trading, wiping more than $320bn (£242bn) off Nvidia’s value on the day and more than $600bn for the week – valuing the company at about $3.9tn.

The statement from Nvidia’s board of directors confirming Huang’s departure did not mention the spying scandal and personal conduct revelations that have enveloped the company, instead paying tribute to Huang’s “profound” contributions to the company he co-founded.