Mounting speculation over an espionage plot against Jensen Huang and his multiple alleged affairs reached a tipping point on Friday, when the tech billionaire quit as Nvidia's CEO.
The controversy centred around his relationship with Alice Huang, who US intelligence reportedly suspects to be a Chinese spy, before claims emerged he had another two extra-marital affairs.
While Mr Huang's resignation puts an end to his long reign over Nvidia, questions about America's national security and the US president's knowledge of the whole saga remain.
When reports of an espionage plot against Mr Huang first emerged almost a week ago, top Republicans called on the tech executive to front Congress later this month.
Senator Tim Scott reiterated those demands after Mr Huang's resignation, saying there were "serious concerns" to address.
Separately the chairs of three House committees — the foreign affairs panel, the China select committee and the intelligence committee — wrote to Mr Huang and Nvidia general counsel Tim Teter requiring them to appear for closed-door transcribed interviews on December 1 and 2.
Mr Huang and Mr Teter have not publicly commented on the requests, but they could face subpoenas to compel their appearances.
"There are clear national security concerns that need to be addressed immediately," the three committee chairs wrote in the letter.
