NEW YORK, Feb 21 ― US stocks ended lower yesterday, with the Nasdaq showing the largest declines as chipmaker Nvidia stumbled ahead of its highly awaited earnings report, while gains in Walmart kept losses on the Dow Industrials in check.

Shares of the chip designer Nvidia tumbled 4.35 per cent, its biggest daily percentage fall since October 17, while the broader Philadelphia semiconductor index declined 1.56 per cent as other chip stocks followed.

Investors are concerned whether Nvidia's quarterly results, expected after markets close today, will justify its expensive valuation, currently at a forward price-to-earnings ratio of just over 32, and continue to fuel the buying frenzy around artificial intelligence (AI) related stocks.

AI-fuelled bets have helped Nvidia become the third-most valuable US company and recently supplant Tesla as Wall Street's most traded stock.

“It is priced to perfection, no matter what they say they are probably going to take money out of it,” said Ken Polcari, managing partner at Kace Capital Advisors in Boca Raton, Florida.

“No matter what they say, the traders are going to lock in profits, the asset managers are going to peel off a piece of their core position and lock in some profits and some of that is even happening today ahead of the number tomorrow.”

Shares in Super Micro Computer, which has surged in recent weeks as the latest stock seen to benefit from AI, fell 1.96 per cent, its second straight decline, after closing down nearly 20 per cent on Friday to snap a nine-session streak of gains.

The S&P 500 lost 30.06 points, or 0.60 per cent, to end at 4,975.51 points, while the Nasdaq Composite lost 144.87 points, or 0.92 per cent, to 15,630.78. The Dow Jones Industrial Average fell 64.19 points, or 0.17 per cent, to 38,56.80.

Walmart closed at a record high and was the best performer on the Dow Industrials after the US retail giant forecast fiscal 2025 sales largely above Wall Street expectations and raised its annual dividend by 9 per cent.

The S&P 500 consumer staples index, which includes Walmart, rose 1.13 per cent as sole advancer of the 11 major S&P sectors, while information technology, down 1.27 per cent was the weakest.

Shares of fellow Dow component Home Depot alternated between modest gains and losses and before closing up 0.06 per cent after the home improvement retailer forecast full-year results below analysts' estimates.

A weeks-long rally on Wall Street stalled last week, as hotter-than-expected US inflation data pushed back market expectations for the timing of a rate cut from the Federal Reserve.

The rate cut is expected in June, according to a slim majority of economists polled by Reuters, who also flagged risk of a further delay in the first cut.

Investors are also awaiting the release of minutes from the Fed's latest policy meeting as well as remarks from a slew of central bank officials later this week.

Smart-TV maker Vizio jumped 16.26 per cent after Walmart said it would buy the company for US$2.3 billion (RM11 billion).

Discover Financial Services shot 12.61 per cent higher on Warren Buffett-backed consumer bank Capital One's plans to acquire the US credit card issuer in a US$35.3 billion deal. Capital One shares edged 0.12 per cent higher.

Declining issues outnumbered advancers by a 1.4 to 1 ratio on the NYSE, while on Nasdaq, decliners topped advancers by 1.9 to 1.

The S&P 500 posted 29 new 52-week highs and 3 new lows while the Nasdaq recorded 111 new highs and 95 new lows.

On US exchanges 11.67 billion shares changed hands compared with the 11.64 billion moving average for the last 20 sessions. ― Reuters