U.S. stock indexes fell sharply Thursday as Wall Street’s frenzy around artificial-intelligence technology faltered some more. The S&P 500 sank 1.6% for its fifth drop in six days after setting an all-time high last week.

Nvidia reported excellent fourth-quarter financial results, beating expectations on the top and bottom lines. Revenue increased 78% to $39.3 billion on particularly strong growth in data center sales, and non-GAAP net income increased 71% to $0.89 per diluted share. The company also provided first-quarter guidance that exceeded estimates.