(Updates with afternoon trading)

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Fed's Williams open to rate cuts depending on data, report

says

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J.M. Smucker falls after quarterly profit miss

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MongoDB ( MDB ) soars after raising annual profit forecast

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S&P 500 +0.22%, Nasdaq +0.18%, Dow +0.31%

By Noel Randewich and Johann M Cherian

Aug 27 (Reuters) -

The S&P 500 climbed to a record high on Wednesday ahead of

quarterly results from Nvidia ( NVDA ), Wall Street's most closely

watched event this week which will test the rally that has

pushed valuations of AI-related companies to levels that some

investors view as too high.

Shares of Nvidia ( NVDA ), the world's most valuable company and the

leading supplier of cutting-edge AI processors, were up 0.1%

ahead of the report, due after the market closes.

With Nvidia ( NVDA ) making up about 8% of the S&P 500, its

financial results affect vast numbers of Americans who use index

investment funds to save for retirement.

"Nvidia ( NVDA ) is going to produce humongous revenue gains over

the next nine months, on top of an already humongous revenue

base," said Jed Ellerbroek, portfolio manager at Argent

Capital.

"Investors should prepare themselves for a world where

Nvidia ( NVDA ) is a double-digit percentage of the S&P 500."

Shares in tech and AI heavyweights Alphabet and

Amazon ( AMZN ), among Nvidia's ( NVDA ) biggest customers, were near

flat, while Microsoft ( MSFT ) rose 0.8% and Meta Platforms ( META )

fell 1%.

Enthusiasm for companies related to AI has fueled big gains

in technology stocks. The S&P 500 now trades at over

22 times expected earnings

, its highest price-to-earnings ratio in four years,

according to LSEG.

Concerns about the pace of the AI really increased last

week after OpenAI CEO Sam Altman warned of a potential AI

bubble.

Nvidia ( NVDA ) options implied a roughly 6% swing for the shares in

either direction following the results.

Investors will closely watch the impact of the Sino-U.S.

trade war on Nvidia's ( NVDA ) China business earlier this year, along

with the effect on forecasts from its recent revenue-sharing

deal with the U.S. government.

The S&P 500 was up 0.22% at 6,480.05 points, and it touched

an intra-day record high.

The Nasdaq gained 0.18% to 21,583.83 points, while the Dow

Jones Industrial Average was up 0.31% at 45,557.67 points.

Eight of the 11 S&P 500 sector indexes rose, led by energy

, up 1.34%, followed by a 0.46% gain in real estate

.

Investors were also watching for developments related to

U.S. President Donald Trump's

attempt to fire

Federal Reserve Governor Lisa Cook, a move likely to face

legal challenges.

If Trump succeeds, he would nominate a replacement to the

central bank's board who could be expected to back his policy

preferences, challenging the central bank's independence.

Investors are pricing in a 25-basis-point interest-rate cut

in September, according to data compiled by LSEG, with most big

brokerages also leaning in that direction.

New York Federal Reserve Bank President

John Williams

said on CNBC it is likely interest rates can fall at some

point but policymakers need to see upcoming economic data to

decide if a rate cut is appropriate at the Fed's September

meeting.

MongoDB ( MDB ) soared 35% after the software-maker raised

its annual profit forecast.

J.M. Smucker fell about 5% after the Jif peanut butter

maker missed first-quarter profit estimates.

Advancing issues outnumbered falling ones within the S&P

500 by a 1.9-to-one ratio.

The S&P 500 posted 27 new highs and 1 new lows; the Nasdaq

recorded 115 new highs and 28 new lows.