Jensen Huang founded accelerated computing company Nvidia (NASDAQ: NVDA) in 1993, and has served as the CEO and president ever since. Nvidia has achieved many breakthroughs under his leadership, but the invention of the graphics processing unit (GPU) in 1999 was particularly momentous.

Quantum computing stocks sank on Wednesday, pausing a year-long rally, after Nvidia CEO Jensen Huang said the technology's practical use was likely two decades away.

The shares of IonQ Inc. and other companies linked to quantum computing tumbled in extended trading on Tuesday after Nvidia Corp. Chief Executive Officer Jensen Huang said “very useful” quantum computers are likely decades away.

Shares of leading firms nose-dive after Nvidia’s Jensen Huang suggests a generational wait for fully functional quantum tech. We’ve been told that the future is now, but it seems it’s not quite here yet—at least not for quantum computing.

Steve Sosnick, Chief Strategist at Interactive Brokers (IBKR), spoke with Quartz for the latest installment of our “Smart Investing” video series.

CEO Jensen Huang said that “very useful quantum computers” are likely 20 years away. The commentary from the tech executive caused an immediate negative reaction in quantum computing stocks, sending popular names like IonQ (IONQ) and Rigetti Computing (RGTI) down between 40% and 50% on Jan.