AMD Tops $1 Trillion Market Cap as AI Chip Rally Lifts Semiconductor Sector

Advanced Micro Devices crossed $1 trillion in market capitalization on Monday, Sept. 21, 2026, with shares hitting a record intraday high of $613.92 after a five-session rally drove the stock up about 24%. AMD jumped as much as 10% on the day. The chipmaker joins Micron Technology, Broadcom, Taiwan Semiconductor Manufacturing Co. and Nvidia among semiconductor firms valued at or above $1 trillion, a group of 15 publicly traded companies worldwide, according to Bloomberg. AMD's year-to-date gain exceeds 180% but trails Nvidia's roughly $5.4 trillion valuation. The rally spread sector-wide: Intel surged 12%, Arm Holdings climbed 14% and the Philadelphia Semiconductor Index rose over 4%. Meta Platforms' Muse AI Agent topped Apple's App Store free chart, lifting Meta shares 7%; Meta accounts for about 5.5% of AMD revenue. AMD's data center segment posted $6.7 billion in second-quarter revenue, more than doubling year over year. CEO Lisa Su targets doubling data center revenue by 2027.