As the HBM technology progresses towards higher-layer stacking, effective heat dissipation and production yield have become pressing challenges for the industry. The latest updates reveal that Samsung Electronics and SK Hynix are set to ramp up the supply of 8-layer HBM4 memory for NVIDIA's next-generation AI accelerator, the Rubin Ultra. This supply boost is scheduled to commence in the second quarter of 2027, marking a shift from the previously favored 12-layer stacking solution. Initially, NVIDIA had contemplated the use of 8-layer HBM4(E) in both the Rubin Ultra and the standard Rubin models to streamline the overall supply chain. However, this strategy has been recalibrated due to concerns that the 12-layer stacking structure could intensify heat dissipation problems, diminish production yield, and compromise supply stability. While 12-layer HBM4 remains a focal point for the current year, it is anticipated that the shipment volume of 8-layer HBM4 will experience a notable surge after the midpoint of next year.