A Chipmaker Nobody Expected Just Joined the Trillion-Dollar Club

Keypoints:

• AMD's market cap crossed $1 trillion on September 21, its stock surging nearly 10% in one session
• It's the fourth US chipmaker to reach the milestone, after Nvidia, Broadcom, and Micron
• AMD shares have nearly tripled since the start of 2026
• The company now sits roughly $352 billion above longtime rival Intel's market cap
• Warrants tied to purchase commitments from OpenAI and Meta played into the valuation math

AMD's stock jumped nearly 10% on September 21, pushing its market capitalization past $1 trillion for the first time and capping a five-day streak that added roughly 25% to its share price. Shares touched an intraday high above $615 before closing near $613, according to CNBC, making AMD the fourth US chipmaker to cross the trillion-dollar line, joining Nvidia, Broadcom, and Micron in a club that held almost no semiconductor names a few years ago.

The number that stings most sits across town from AMD's own rally. AMD's roughly $1 trillion valuation now sits about $352 billion above Intel's, the company that spent decades as the dominant force in x86 computing and once dwarfed AMD in size many times over. 

AMD's underlying results back up some of the enthusiasm too, second-quarter revenue hit a record $11.5 billion, up 50% year over year, with data center revenue more than doubling to $6.7 billion.

Part of the valuation story runs through warrants rather than the stock price alone. AMD's biggest customers, OpenAI and Meta, hold warrants tied to purchase commitments, each needing to buy 6 gigawatts of AMD chips for those warrants to fully vest. 

Counting those warrants at full value, one analysis put AMD's valuation closer to $1.09 trillion even before Monday's rally. The broader chip sector moved together that day too, the PHLX Semiconductor Index rose more than 3%, and Intel and Arm Holdings both jumped 10% on the same session, suggesting the rally reflected sentiment across AI infrastructure broadly rather than AMD alone, with some of that optimism tied to an upcoming Trump-Xi summit.

The gap with the category leader remains wide regardless. Even at $1 trillion, AMD trails Nvidia's roughly $5.5 trillion market cap by a wide margin, and Nvidia still commands an estimated 81% of the AI accelerator market against AMD's roughly 13%, according to IDC, with Nvidia's data center revenue alone running $75.2 billion in a single quarter against AMD's entire company revenue of $11.5 billion. 

Market cap reflects expectations about the future as much as today's numbers, and AMD crossing this threshold says as much about how much AI infrastructure spending investors expect to keep flowing as it does about the company's current earnings.