US equity indexes fell in midday trading on Thursday as a sell-off in semiconductor firms hit technology after Nvidia (NVDA) released quarterly results overnight.

The Nasdaq Composite sank 1.8% to 22,732.3, the S&P 500 dropped 1.1% to 6,870.4, and the Dow Jones Industrial Average declined 0.5% to 49,256.7.

All but three sectors, energy, financials, and real estate, declined. Communication services, consumer discretionary, and materials were among the steepest decliners.

Nvidia reported a year-over-year jump in fiscal Q4 adjusted earnings and revenue late Wednesday and issued a Q1 revenue outlook above analysts' expectations. Nevertheless, shares gave up after-hours gains accrued late Wednesday, and fell 4.7% in the regular session after midday on Thursday, the worst performer on the Dow.

Among stocks with a market capitalization of more than $200 billion, nine out of the 10 worst performers were chipmakers, including Broadcom (AVGO), Applied Materials (AMAT), and ASML (ASML), data compiled by Finviz showed.

Salesforce (CRM) shares rose 2.8%, the biggest outperformer on the Dow, after the customer relationship management platform reported overnight fiscal Q4 results above market expectations.

Paramount Skydance (PSKY) reported a wider Q4 loss but stronger-than-expected growth in year-over-year revenue late Wednesday. "We like the operational momentum under new management, with the DTC segment showing strength," CFRA told MT Newswires while acknowledging the company's mixed results. Shares jumped 9.2%, the top gainer on the S&P 500.

In economic news, US initial jobless claims rose to 212,000 in the week ended Feb. 21 from an upwardly revised 208,000 in the previous week, compared with expectations for 216,000 in a survey of analysts compiled by Bloomberg.

Meanwhile, the Kansas City Fed monthly manufacturing index rose to 5 in February from 0 in January, higher than expectations for an increase to 2 in a Bloomberg-compiled survey.

Most US Treasury yields declined, with the two-year down 2.7 basis points to 3.44%. The 10-year yield dropped 2.7 basis points to 4.02%.

In precious metals, gold futures fell 0.7% to $5,190.6 per troy ounce, and silver futures slumped 4.8% to $86.59 per troy ounce.

In energy markets, West Texas Intermediate crude oil futures jumped 1.7% to $66.53 a barrel.