Major U.S. stock indices closed significantly lower as an initial rally led by Nvidia's earnings beat turned into a broad selloff. The Nasdaq Composite dropped 2.15%, while the S&P 500 and Dow Jones Industrial Average fell 1.55% and 0.84%, respectively. Nvidia, which surged over 5% at the market open, closed down 2.97% at $180.98. The downturn affected high-beta tech and semiconductor stocks, with Micron plummeting 10.87%, AMD losing 7.84%, and Western Digital declining 8.92%. Bitcoin also fell, reaching $86,538, marking its lowest point since April.