Memory chips have become the bottleneck of the AI boom, and that is very good news for Micron and its investors — and a problem for anyone trying to buy chips.

• Micron's entire output is already sold out, with data center customers asking for about 50% more than the company can promise to deliver.
• Micron CEO Sanjay Mehrotra put it bluntly: without memory, there is no AI.
• The company is pouring $250 billion into US plants and research, including two huge new factories near its Idaho headquarters, the first due to start production in mid-2027.
• Memory is no longer a cheap commodity bought from the lowest bidder — customers now design their chips together with Micron, and 16 major buyers have signed five-year deals to lock in supply.
• The boom is spreading past data centers to self-driving cars, robots, and AI gadgets.

Outlook: Tight supply and long-term contracts should keep memory prices and Micron's earnings strong well past the usual boom-and-bust cycle.