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AT&T ( T ) rises after beating subscriber-addition estimates

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Enphase Energy ( ENPH ), Texas Instruments ( TXN ) up after results

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Visa falls after missing revenue growth forecasts

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Rivian falls; will face trial in Tesla trade secrets theft

case

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Futures down: Dow 0.42%, S&P 500 0.69%, Nasdaq 1.04%

(Updated at 6:54 a.m. ET/1054 GMT)

By Ankika Biswas and Lisa Pauline Mattackal

July 24 (Reuters) -

Wall Street futures fell on Wednesday, with those tracking

the tech-heavy Nasdaq recording the steepest losses after weak

quarterly earnings from Tesla and Alphabet, as investors

questioned the dominance of Big Tech and euphoria around AI.

Tesla slumped 8% in premarket trading and looked

set to lose roughly $60 billion in market value, if losses hold,

after the EV maker reported its lowest profit margin in over

five years and missed expectations for second-quarter earnings.

Google parent Alphabet, too, shed 3.1% despite

beating expectations for second-quarter revenue and profit, as

investors focused on a slowdown in advertising growth and the

company flagged high capital expenses for the year.

Alphabet's losses underscore the high earnings bar for

the so-called Magnificent Seven, the set of megacap tech stocks

that have notched double- to triple-digit percentage gains so

far in 2024, riding on optimism around AI adoption and an early

start to Federal Reserve rate cuts.

"The first view on Big Tech earnings wasn't inspiring," said

Ipek Ozkardeskaya, senior analyst at Swissquote Bank.

"Two of the Magnificent Seven stocks failed to create

euphoria when they reported their Q2 results. The

less-than-ideal set of earnings comes at a time when investors

are questioning whether the AI rally has gotten ahead of

itself."

Results from the tech giants, which have driven broader

indexes to all-time highs over the first half of the year, will

be key to determine if the Wall Street rally has steam to spare,

even as market participants have grown wary of the valuation of

these companies and started shifting to underperforming sectors.

Other megacaps such as Microsoft ( MSFT ), Amazon.com ( AMZN )

, Meta Platforms ( META ) and Nvidia ( NVDA ) were down

between 0.3% and 2.2%.

Wall Street's main indexes had closed lower on Tuesday,

although the Russell 2000 ended 1% higher. Futures

tracking the small-cap index fell 0.3% on Wednesday.

Later in the day, investors will parse the S&P Global's

flash PMI and new home sales numbers. But the key economic

release of the week is Friday's personal consumption

expenditures data, which can corroborate if market bets on the

monetary policy path are headed in the right direction.

Traders have priced in a nearly 92% chance the U.S. Federal

Reserve will cut interest rates by 25 basis points by its

September meeting and expect two rate cuts this year, according

to LSEG data.

At 6:54 a.m. ET, Dow e-minis were down 170

points, or 0.42%, S&P 500 e-minis were down 38.75

points, or 0.69%, and Nasdaq 100 e-minis were down 207

points, or 1.04%.

In other earnings, AT&T ( T ) gained 3.1% after beating

forecasts for wireless subscriber additions in the second

quarter, as the telecom operator's higher-tier unlimited plans

attracted customers.

Solar inverter maker Enphase Energy ( ENPH ) jumped 5.7%

after beating estimates for second-quarter operating profit,

while Texas Instruments ( TXN ) rose 2.8% after a second-quarter

profit beat.

Visa dropped 3.4% after its third-quarter revenue

growth fell short of expectations, a rare miss for the world's

largest payments processor, while Thermo Fisher Scientific ( TMO )

dropped 3% after results.

Meanwhile, shares of Rivian Automotive ( RIVN ) fell 3.3% as

the EV maker will go on trial over allegations it encouraged its

employees who defected from Tesla to steal trade secrets.