Stock 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 BloombergStock Market Today: Nasdaq Edges Lower; TSMC in Focus — Live Updates The Wall Street Journal