The US stock market enters its busiest earnings week this cycle, with roughly one-third of S&P 500 companies reporting results. Alphabet and Microsoft are scheduled to release quarterly figures on Wednesday, followed by Amazon on Thursday. Investors are closely watching capital expenditure guidance and returns on AI investments from these tech giants, as hyperscaler spending is projected to reach approximately $800 billion this year. The Federal Reserve will announce its rate decision on the same day. Futures markets indicate less than a 10% probability of a rate hike at this meeting, while pricing in about an 80% likelihood for December. The convergence of major tech earnings and central bank policy creates a critical test for the ongoing AI-driven rally. Sentiment has already shown strain following disappointing results from Meta and Lam Research. The Nasdaq recorded its largest single-day decline since June on Thursday, reflecting growing investor scrutiny over AI valuations and spending sustainability.