Fears that the artificial-intelligence boom may not pay off as quickly as hoped sent chip stocks tumbling across the United States and Asia, with South Korea's main index briefly suspended after a steep plunge.
Trading on South Korea's Kospi index was paused for about twenty minutes on Tuesday after it slid eight percent, before slipping further to around ten percent lower once the halt lifted. The selloff was led by technology heavyweights, with Samsung Electronics and SK Hynix each dropping more than ten percent.
The Kospi has triggered such circuit breakers eight times this year, a mechanism designed to halt panic selling. The index had more than doubled from January to mid-June before giving back roughly a third of its value.
The shock followed a rough session in New York, where Nvidia fell about five percent and surrendered its crown as the world's most valuable company to Apple. Nvidia's drop came after reports that it was in talks to commit around two hundred and fifty billion dollars to a massive OpenAI data-centre project, prompting questions about how quickly AI spending can translate into profit.
Japan's Nikkei 225, also weighted toward technology, fell nearly four percent. SK Hynix's US-listed shares dropped below their recent offer price, underscoring how fragile the rally had become.
Analysts have long warned that hundreds of billions of dollars in AI investment must eventually yield returns. The selloff suggests some investors are losing patience, even as companies insist demand still outstrips supply.
Chinese challengers add another wrinkle. Memory maker CXMT's blockbuster debut highlights growing competition, even as the broader market questions whether the AI trade has run too far, too fast. For now, volatility has returned to a sector that had seemed impervious to doubt.
The coming weeks will test whether this is a healthy correction or the start of a broader pullback. With retail investors heavily exposed in markets like South Korea, the swings are likely to stay sharp, and any fresh signal on AI demand could move trillions in market value within a session.
The episode is a reminder that technical systems rarely fail in isolation; the consequences tend to cascade into regulation, trust, and the incentives that govern the next round of investment.
For policymakers, the challenge is to set guardrails without chilling the innovation that made the technology valuable in the first place.
Engineers on the ground note that the failure mode was foreseeable, the kind of edge case that slips through when speed of delivery is prioritised over depth of review.
