*

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

says

*

J.M. Smucker falls after quarterly profit miss

*

MongoDB ( MDB ) soars after raising annual profit forecast

*

S&P 500 +0.24%, Nasdaq +0.21%, Dow +0.32%

(Updates with closing price moves)

By Noel Randewich

Aug 27 (Reuters) - The S&P 500 notched a record high

close 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, bounced between

gains and losses before ending down 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 were mixed, with

Microsoft ( MSFT ) gaining nearly 1% and Meta Platforms ( META )

dipping almost 1%. They, along with Alphabet and

Amazon ( AMZN ), are among Nvidia's ( NVDA ) biggest customers.

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 rally 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 climbed 0.24% to end the session at 6,481.40

points, exceeding its previous record high close on August 14.

The Nasdaq gained 0.21% to 21,590.14 points, while the

Dow Jones Industrial Average rose 0.32% to 45,565.23 points.

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

energy, up 1.15%, followed by a 0.48% gain in

information technology.

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 38% after the software-maker raised

its annual profit forecast.

J.M. Smucker fell 4.4% after the Jif peanut butter

maker missed first-quarter profit estimates.

Advancing issues outnumbered falling ones within the S&P

500 by a 2.2-to-one ratio.

The S&P 500 posted 28 new highs and 1 new lows; the

Nasdaq recorded 127 new highs and 35 new lows.

Volume on U.S. exchanges was relatively light, with 14.0

billion shares traded, compared to an average of 16.9 billion

shares over the previous 20 sessions.