Nvidia's (NVDA) fourth quarter earnings beat and better-than-expected first quarter revenue outlook failed to lift the stock on Thursday as concerns about how big bets on AI will pay off continued to swirl. Initial gains after-hours for Nvidia stock gave way to bearish sentiment for the world's largest company by market cap. The lukewarm reception to Nvidia's results dragged on the tech-heavy Nasdaq Composite (^IXIC) and S&P 500 (^GSPC) as investors wanted more details about Nvidia's upbeat forecast and w ...