AI 支出担忧引发美股科技股连日下跌，Intel 盘中跌逾 30%

Tech stocks tumbled for the second day in a row as concerns rise over the hundreds of billions of dollars firms are investing in artificial intelligence (AI).

Shares in Intel plummeted by as much as 30% on Friday, following Google owner Alphabet's stock price plunging by more than $500bn (£374bn) in the previous day's trading.

Other tech stocks including Reddit and Amazon also fell, while the Nasdaq index of the largest tech firms listed in the US, sank over 3.5%.

While tech firms are spending big on AI, their earnings are not always meeting analysts' expectations, spooking investors and creating fears of an AI bubble.

Major tech companies have ramped up artificial intelligence spending, with Meta, Alphabet, Oracle, Amazon, and Microsoft committing to spending $800.6bn between them in 2026.

Alphabet's stock market value plunged on Thursday after it revealed its own AI summaries were affecting its core search advertising revenue.

At the same time, Alphabet expects to spend up to $205bn this year on investments, almost entirely related to AI.

Alphabet stock continued to fall in early trading, down 1% after Thursday's massive slide.

The bigger losses on Friday were elsewhere, with Intel on track to lose more than $130bn in value as its shares continued to fall in Friday trading.

The chip maker said it planned to increase spending on AI despite weaker demand for computers.

On Thursday, Intel's finance chief David Zinsner said the firm did not expect to bring in more cash than it spent this year and forecast lower-than-expected revenue for its fourth quarter.

"Looking ahead, we see the PC slowdown continuing at least through the first half of next year," he said in the chip maker's third quarter earnings report.

In the earnings call, he said the firm had significantly ramped up investment in equipment in the third quarter and expected that to be "even more significant" in the following three months.

Amazon shares fell as far as 6% in overnight trading after the company's reported earnings fell short of investors' expectations.

Amazon on Thursday revealed it had also spent more cash that it was making, and that spending had increased six-fold over the span of three months.

The company has committed to spending $220bn this year alone, putting the money towards investments such as AI data centres, network equipment, and servers.

Shares recovered slightly from the overnight fall but were still down about 1.6% in Friday trading.

Reddit stock was down by 26%, after the social media platform revealed weaker-than-expected daily user figures and warned that Google's growing AI-driven search was hurting referral traffic.

Stock in online game platform Roblox also fell, down by nearly 20%, as its daily active user numbers dropped.

Several major tech firms have reported earnings this week, including Microsoft, and analysts said there were questions about the payout from the huge investments in AI.

Chris Low, from investment management firm FHN Financial, said the bulk of what was happening in the stock market was in reaction to some of the biggest tech players such as Amazon and Google.

He told Reuters the companies were "showing some pretty significant growing pains as they aggressively pursue the AI build-out".

"The thinking is that these signs suggest that the entire sector is going to slow down."

Many analysts have been debating the possibility of an AI bubble in the stock market.

The worry is that some tech firms do not justify their sky-high valuations because the cost of building AI data centres and developing the software will end up being greater than the money they predict they will make from it.

Kathleen Brookes, research director at trading firm XTB, said there have been many ups and downs in AI trade in recent months.

"Investors have turned ruthless, punishing any signs of disappointment in [third quarter] earnings," she said.

"The AI trade has had a good run in recent years, but now investors want payback, and companies like Alphabet and Intel are in the crosshairs."

However, stock market values for many of these companies remain well above where they were a year ago.

While the Nasdaq is down 3.5% in Friday trading, it is up 7.6% over the last year. Similarly Amazon is up nearly 7% over the past 12 months, while Alphabet is down 1.6%.

Brookes noted that November is typically a strong month for stocks.

"If we see AI stocks continue to struggle in the coming days, it could suggest the AI trade is past its peak, and investors will be looking for a new theme to drive markets," she said.