Analysis
The Nasdaq Composite closed at a record high above 27,200 on September 22, driven by a rally in memory chip stocks: SanDisk surged more than 8% intraday to briefly top $1,900 a share, while Micron and SK Hynix's US-listed shares each gained more than 3%, according to Yahoo Finance and Invezz.
A Supply Crunch, Not Just Demand
The rally reflects a persistent global memory-chip shortage Pulse has tracked since August, when tight DRAM and NAND supply -- driven substantially by AI data center demand for the same chips -- helped push Xiaomi's profit down 43% as smartphone component costs rose faster than the company could pass them on to consumers. The same dynamic now cuts the other way for the chipmakers themselves: memory suppliers are raising prices and racing to expand capacity as AI data centers compete directly with consumer electronics for the same limited DRAM and NAND output.
SanDisk's stock is now up more than 570% in 2026, per Forbes, one of the year's largest single-stock moves among any US semiconductor name, while Micron is trading near an all-time high on the same tight-supply dynamic. Falling oil prices and easing near-term rate pressure also supported broader tech valuations the same session, but the memory names specifically outperformed on the AI-driven supply story rather than macro tailwinds alone.
The rally is a direct bet that AI data center memory demand keeps outpacing new fab capacity through 2027 -- a bet that depends on hyperscalers' AI capex plans continuing on their current trajectory, the same capex plans this week's California data-center laws and other regulatory pushback are aimed at slowing at the margins.
It also lands the same week AMD crossed its own $1 trillion market-cap milestone on AI-chip demand, and together the two moves show the AI rally has broadened well past Nvidia and the logic chipmakers into memory suppliers that were, until this year, treated as commodity, cyclical businesses rather than AI infrastructure plays in their own right.
