US STOCKS-Wall Street indexes notch record-high closes as Intel soars on Nvidia stake

By Abigail Summerville and Sukriti Gupta

Sept 18 (Reuters) - Wall Street's main indexes posted record-high closes on Thursday, a day after the U.S. Federal Reserve delivered a quarter-point interest rate cut, while chipmaker Intel rose after Nvidia decided to build a stake in the company.

Intel INTC.O clinched its biggest daily gain since October 1987, jumping 22.8% after Nvidia NVDA.O said it would invest $5 billion in the struggling U.S. chipmaker. Peer Advanced Micro Devices AMD.O slipped 0.8%.

Nvidia rose 3.5%, recovering losses from Wednesday when a report said Chinese tech firms might stop buying its chips.

The moves boosted a broader semiconductor .SOX index up 3.6%, and also lifted the tech-heavy Nasdaq and the S&P 500 technology sector .SPLRCT up 1.36%. Seven of the 11 S&P 500 sectors gained.

Meanwhile, the small-cap Russell 2000 index .RUT notched its first record high close since November, at 2,466 points. Small-cap companies are likely to perform better in a low interest-rate environment.

On Wednesday, Fed Chair Jerome Powell emphasized that the softening jobs market was a priority and indicated more reductions could follow at upcoming policy meetings.

"We are looking for support for economic growth and justification of stretched valuations and the prospect of lower interest rates helps that," said Sam Stovall, chief investment strategist at CFRA Research.

The Dow Jones Industrial Average .DJI rose 124.10 points, or 0.27%, to 46,142.42, the S&P 500 .SPX gained 31.61 points, or 0.48%, to 6,631.96 and the Nasdaq Composite .IXIC gained 209.40 points, or 0.94%, to 22,470.73.

The biggest S&P sector decliners were consumer staples .SPLRCS and consumer discretionary .SPLRCD stocks.

New data showed that the number of Americans filing new applications for unemployment benefits fell last week, but the labor market has softened as both demand for and supply of workers have diminished.

The rate cut is expected to add to Wall Street's recent rally, boosted by monetary policy easing hopes and a revival of AI-linked stock trading. Investors are pricing in about 44.2 basis points in cuts by end-2025, data compiled by LSEG showed.

Among stocks, CrowdStrike CRWD.O gained 12.8% after at least nine brokerages raised their price target on the stock.

Shares of Darden Restaurants DRI.N fell 7.7% after the Olive Garden parent reported weak quarterly results.

Advancing issues outnumbered decliners by a 1.87-to-1 ratio on the NYSE, and by a 2.5-to-1 ratio on the Nasdaq.

The S&P 500 posted 31 new 52-week highs and eight new lows while the Nasdaq Composite recorded 156 new highs and 42 new lows.

Volume on U.S. exchanges was 19.30 billion shares, compared with the 16.67 billion average for the full session over the last 20 trading days.