Semiconductor stocks are down significantly in pre-market trading following a dismal earnings report and forecast from sector giant Intel after the previous day's close. The company's stock fell over 18% in after-hours trading after it warned of a slump in PC demand and a costly factory shutdown in Israel. This adds to broader concerns about the high cost of AI infrastructure investments, which were amplified by disappointing results from Google's parent company, Alphabet, during the prior trading session.