Chip stocks drop on report US plans to tighten China curbs BBC.comStock market news today: Dow falls 500 points, Nasdaq slides as tech rout continues Yahoo FinanceWall Street ends sharply lower as anxiety rises, earnings heat up ReutersChip Stocks Sell-Off Fuels Calls To Buy the Dip InvestopediaUS Floats Tougher Trade Rules to Rein In China Chip Industry Bloomberg