U.S. stocks ended mixed on Sept. 23, with the Dow Jones Industrial Average down 0.32% intraday while the Nasdaq Composite rose 0.80% and the S&P 500 gained 0.05%. Among notable stocks, SanDisk (SNDK) climbed 6.95%, Micron (MU) advanced 5.10%, Riot Platforms (RIOT) rose 3.58%, SKHY gained 3.32%, MARA added 2.55%, and Intel (INTC) increased 2.11%, based on Binance market data.