U.S. stocks closed sharply lower on Friday, ending October with a broad tech sell-off as Intel's disappointing forecast and Amazon's ballooning spending on artificial intelligence deepened investor doubts about whether the AI boom will pay off.
The Nasdaq Composite fell about 2.9% to roughly 25,440, its worst day since early June. The S&P 500 lost about 1.8% to around 7,580, and the Dow Jones Industrial Average dropped about 1.1%, or more than 570 points. Companies in the Nasdaq 100 lost more than $1 trillion in market value in a single session, pushing the index close to correction territory.
Intel suffers worst day on record
Intel shares plunged about 29%, the steepest one-day drop in data going back to the 1980s, after the chipmaker forecast lower fourth-quarter sales and profit and said it would burn cash this year amid a weak PC market, manufacturing hurdles and heavy spending to expand production.

"Our customers began signaling a PC slowdown based on the memory prices and availability," Intel CEO Lip-Bu Tan said. The warning rippled across the chip sector: AMD fell about 10%, Nvidia lost around 4% and the Philadelphia Semiconductor Index dropped more than 7%. Dell and HP also slid sharply, and the world's largest chipmakers and equipment suppliers shed about $1 trillion in combined value.
AI spending under scrutiny
Amazon fell as much as 10% in after-hours trading Thursday after reporting a sharp cash outflow and signaling higher capital spending next year, before paring losses to close down about 1.4% on Friday. Alphabet slipped another 1.4% a day after losing about $500 billion in market value, its worst day ever.
Reddit tumbled about 28% after CEO Steve Huffman warned that daily active unique visitors could fall by a low double-digit percentage in the fourth quarter. Coinbase sank about 13% after a $6.3 billion heist at the crypto exchange Binance, and Bitcoin fell about 2%.
"A lot of them kind of got ahead of themselves. It's all earnings-based and right now, they're not producing," said Joe Saluzzi, co-manager of trading at Themis Trading. "It doesn't kill the whole story, it's pretty much a reset."
Rates and oil add pressure
Higher borrowing costs are also weighing on tech companies that are borrowing heavily to finance data centers, with the 10-year Treasury yield near 4.9%. The Federal Reserve held rates steady this week, but traders now expect hikes totaling more than 50 basis points by mid-2027, according to LSEG data.
Oil prices climbed on signs that the U.S. could resume strikes on Iran, and Exxon Mobil and Chevron rose after beating third-quarter profit estimates.
The Nasdaq ended October with a monthly loss of about 5%, snapping a two-month winning streak, while the Dow posted a gain for the month.