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* Futures: Dow up 0.19%, S&P down 0.09%, Nasdaq down

0.69%

July 28 (Reuters) - Nasdaq futures fell on Tuesday,

mirroring a cautious mood across global markets toward AI chip

stocks on concerns about hefty corporate spending and rising

Chinese competition, ahead of earnings from some of the biggest

companies on Wall Street.

Chip bellwethers such as Nvidia ( NVDA ) fell 1.1%, Micron

slid 4.6% and Applied Materials ( AMAT ) lost 3.5% in

premarket trading, while U.S.-listed shares of Taiwan's TSMC

and Korea's SK Hynix fell 2.6% and 4%,

respectively.

Global markets have become increasingly volatile this month

as investors scrutinized the need for more corporate spending on

AI infrastructure, such as semiconductors that underpinned

strong gains in chip stocks in the previous quarter.

Roundhill's Memory Exchange Traded Fund lost 6.6%

on Tuesday and has been trading below its 50-day moving average

for the past two weeks, reflecting a weak short-term momentum,

while the Philadelphia SE Semiconductor Index has fallen

over 20% from its all-time high hit in June.

Signs that Wall Street's biggest companies such as Alphabet

and Tesla are running out of cash to fund

their ambitions have also made markets nervous, while China

showcases cheaper AI models and deepens its presence in the

competitive semiconductor industry.

When AI hyperscalers Amazon.com ( AMZN ), Meta,

Apple ( AAPL ) and Microsoft ( MSFT ) report earnings later this

week, investors will be keen to see if their investments, worth

over several hundred billion dollars, are yielding returns. The

reports are also expected to offer clues on the demand for chips

and other AI infrastructure.

Shares of the four U.S. companies were marginally higher in

premarket trading on Tuesday.

At 04:27 a.m. ET, Dow E-minis were up 100 points,

or 0.19%, and S&P 500 E-minis were down 6.5 points,

or 0.09%. Nasdaq 100 E-minis were down 194.5 points,

or 0.69%.

The Federal Reserve is also due to announce its interest

rate verdict on Wednesday at the end of its two-day meeting.

Traders only see a 37.4% likelihood for a rate hike this week,

according to LSEG-compiled data, but are confident that

borrowing costs could rise by at least 25 basis points by the

end of the year.

Offering both the Fed and investors some relief, oil prices

fell 2.8% to a one-week low as a fragile ceasefire between the

U.S. and Iran held up despite drone attack reports out of Saudi

Arabia, Jordan and Iraq.

U.S. President Donald Trump said the United States was

having "good talks" with Iran and there was a chance of a deal

to end the conflict.