Quantum computing companies have surged recently but Nvidia CEO Jensen Huang had a disappointing message for the sector.

Addressing a question from an audience member, Huang said 15 years would probably be on the "early side" and that 30 years would likely be on

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 long wait outlined by Huang for "very useful quantum computers" throws cold water on a sector that was already expected to spend millions more on the technology,