Stock market today: Dow loses 600 points to kickoff September as Nvidia sell-off continues Yahoo FinanceDow closes 600 points lower to begin September, S&P 500 drops 2%: Live updates CNBCHeard on the Street Recap: September Swoon The Wall Street JournalDow falls by more than 600 points as September turns ugly CNNDow sinks 600 points, Nasdaq drops 3.2% in first Sept. session Yahoo Finance