Quantum-computing stocks fell again Friday, extending the previous session’s losses as investors were left disappointed by a Nvidia event aimed at celebrating the technology.The artificial-intelligence chip maker’s Quantum Day was lacking in major announcements and the formerly highflying stocks tumbled.

Nvidia CEO Jensen Huang on Thursday walked back comments he made in January, when he cast doubt on whether useful quantum computers would hit the market in the next 15 years.

The chipmaker NVIDIA held its annual conference in Silicon Valley this week. Among the major announcements: it chose Boston to be the site of its first-ever research center for quantum computing, opening later this year.