U.S. Stocks Hit New High, Led by AI Chip Companies

America's main stock baskets all climbed on Oct. 6. The S&P 500, covering 500 big companies, passed 7,800 for the first time, up 0.58%. The Nasdaq, heavy on tech firms, rose 0.45% to its highest close ever. The Dow, with 30 household names, rose 0.49%, just below its August peak. AI chip firms Marvell, AMD and Broadcom led the way.