Microsoft shares plunged ~12% last week, erasing $440 billion in market cap, the second-largest single-day drop ever, after Q2 FY26 earnings revealed a 66% capex surge to $37.5–40 billion on AI data centers and NVIDIA GPUs. Azure grew 39% (cloud >$50 billion), but investors worry about returns lagging spend, heavy OpenAI reliance (45% RPO), and rapid GPU depreciation.