Intel Jumps 12%, Arm 17% as Meta's Muse AI Agent Ignites CPU Chip Rally; AMD Tops $1 Trillion

Intel (INTC) rose 12% and Arm (ARM) 17% on September 21, 2026, while AMD (AMD) gained 9.9% to close at $615.52, pushing its market capitalization past $1 trillion — the 14th U.S. company to reach that milestone and AMD's first record close since June 30. The rally followed enthusiasm for Meta Platforms' (META) Muse AI agent, which has been the top free app on the U.S. iPhone App Store for three days, per Sensor Tower. Agentic AI's autonomous task execution is expected to lift inference demand for CPUs alongside GPUs. Intel CEO Lip-Bu Tan said last week the company can meet only about 50% of customer demand. Arm projects server CPU market growth above 35% annually to $120 billion by 2030; AMD forecasts 50% growth and a $2,200 billion opportunity. KeyBanc's Justin Patterson cited Meta's distribution and data advantages, while Amazon (AMZN) has blocked Muse from shopping on its site.