(Updates close with volume, shares moves, other details)

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Microsoft ( MSFT ) advances after OpenAI restructuring deal

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Key results from megacap names due this week

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Nvidia will build AI supercomputers for US energy

department

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Indexes: Dow up 0.3%, S&P 500 up 0.2%; Nasdaq up 0.8%

By Caroline Valetkevitch

NEW YORK, Oct 28 (Reuters) - All three major U.S. stock

indexes posted record closing highs again on Tuesday as Nvidia

shares gained following news it will build artificial

intelligence supercomputers for the U.S. energy department, and

as investors were optimistic about corporate earnings ahead of

key results from megacaps this week.

Nvidia CEO Jensen Huang said the company will build seven

supercomputers for the U.S. Department of Energy, and said the

company has $500 billion in bookings for its AI chips.

Nvidia's stock closed up 5%, adding over $230 billion in

market value and putting the company on the verge of becoming

the first worth $5 trillion.

Also boosting the market, Microsoft's ( MSFT ) shares gained 2%

after the company reached a deal that allows OpenAI to

restructure into a public benefit corporation while giving

Microsoft ( MSFT ) a stake of 27% in the ChatGPT maker.

Quarterly results are expected this week from Apple ( AAPL ),

Microsoft ( MSFT ), Alphabet, Amazon ( AMZN ), and Meta

Platforms ( META ). Investors are anxious for details from the

companies on AI spending. Shares of Apple ( AAPL ) ended up just 0.1%,

with the company earlier crossing $4 trillion in market value

for the first time.

"Momentum and earnings are pushing the market higher," said

Peter Cardillo, chief market economist at Spartan Capital

Securities in New York.

"Earnings have been good," he said. "Of course, we're

waiting for the big tech stocks."

Investors were also digesting trade-related news. The Wall

Street Journal said U.S. President Donald Trump and Chinese

leader Xi Jinping will discuss a trade framework to reduce U.S.

tariffs on Chinese goods in exchange for Beijing's commitment to

curb exports of fentanyl precursor chemicals.

The Dow Jones Industrial Average rose 161.78 points,

or 0.34%, to 47,706.37, the S&P 500 gained 15.73 points,

or 0.23%, to 6,890.89, and the Nasdaq Composite gained

190.04 points, or 0.8%, to 23,827.49.

Trump lavished praise on Japan's first female leader, Sanae

Takaichi, in Tokyo on Tuesday. They signed a deal to bolster

supplies of critical minerals and rare earths, as their nations

seek to reduce China's dominance of some areas of key electronic

components.

QUARTERLY EARNINGS UP

With results in from 180 of the S&P 500 companies,

third-quarter earnings are estimated to have increased 10.5%

from the year-ago period, up from earlier estimates for the

quarter, according to LSEG data.

On Wednesday, the Federal Reserve is widely expected to

announce a 25-basis-point interest rate cut. Investors will be

keen to get any details on the rate outlook, especially given

that the U.S. government has been shut down for nearly a month,

delaying crucial economic data and forcing traders to rely on

private releases and corporate announcements.

A preliminary estimate of an ADP National Employment Report

showed the U.S. economy added an average of 14,250 jobs in the

four weeks ending October 11.

Even though the ADP data seemed to be positive, it was tempered

by layoff announcements by big companies such as Amazon ( AMZN ) and

others, analysts said.

Shares of United Parcel Service ( UPS ) jumped 8% after the

company posted quarterly results in a sign its overhaul is

making headway. UPS has been shuttering hundreds of facilities,

slashing thousands of jobs and offering buyouts to its union

drivers as part of its largest-ever overhaul, which aims to

reduce costs by $3.5 billion in 2025.

After the closing bell, shares of Visa edged higher after

the company reported a rise in quarterly adjusted profit amid

strong transaction volumes. Visa's stock ended the regular

session down 0.3%.

Declining issues outnumbered advancers by a 1.35-to-1 ratio on

the NYSE. There were 613 new highs and 102 new lows on the NYSE.

On the Nasdaq, 1,868 stocks rose and 2,862 fell as declining

issues outnumbered advancers by a 1.53-to-1 ratio.

Volume on U.S. exchanges was 20.5 billion shares, compared

with the 20.96 billion average for the full session over the

last 20 trading days.