South Korea's Kospi index surged over 17% on Friday, marking its largest single-day gain on record and defying regulators' attempts to curb extreme volatility. The benchmark, dominated by chip giants Samsung Electronics and SK Hynix, has seen five of its ten biggest daily moves since March, while three of the four steepest declines occurred in the past five weeks, according to LSEG data. Friday's rally surpassed the 12% surge recorded during the 2008 financial crisis.

The rebound followed announcements from Amazon and Microsoft that they have increased capital spending due to rising memory costs amid a global supply shortage, as AI demand continues to outpace production capacity. The news reignited demand for Korean chipmakers and eased concerns about the sustainability of massive AI infrastructure spending that had recently pressured their shares.

"The gamification of the stock market has led to such gyrations driven less by fundamentals but by news flows and fads," said Peter S. Kim, global strategist at KB Financial Group. For policymakers, the volatility remains a major headache, prompting increasingly stringent restrictions on single-stock leveraged exchange-traded funds tracking the major chipmakers.