HBM’s Thermal Wall: Why One Korean Chipmaker Controls the Pace of the AI Build-Out
6 min readSK Hynix controls 62% of global HBM shipments and sold out its entire 2026 production by mid-2025. Here is why High Bandwidth Memory — not TSMC node capacity or CoWoS packaging — has become the single binding constraint on the AI infrastructure build-out, and what Samsung’s 18-month qualification failure reveals about the difficulty of meeting NVIDIA’s thermal and power standards.