South Korea's Kospi dives more than 5%, SK hynix down 10%

South Korea's Kospi index plunged 5.6 percent to 7,058.82 in early trade, with chipmaker SK Hynix tumbling 10.1 percent despite its US ADR rising almost 13 percent on its New York debut on Friday. The sharp reversal highlights volatility in global semiconductor and tech stocks.