The Nasdaq-100 experienced a significant downturn, with the QQQ ETF falling sharply due to a wave of disappointing earnings reports and guidance from key mega-cap technology companies. Concerns over heavy spending on artificial intelligence and its uncertain returns, coupled with a weak forecast for the PC market, have unsettled investors. Specifically, weaker-than-expected results or outlooks from Amazon, Intel, and Alphabet have been the primary catalysts for the broad-based tech sell-off.