Even with organic substrates, SPHBM4 remains stacked memory with a specialized base logic die and tight coupling to accelerators.

High bandwidth memory has evolved around extremely wide parallel interfaces, and that design choice has defined both performance and cost constraints.

HBM3 uses 1024 pins, a figure that already pushes the limits of dense silicon interposers and advanced packaging.

The JEDEC Solid State Technology Association is developing an alternative known as Standard Package High Bandwidth Memory 4 (SPHBM4), which reduces the physical interface width while preserving total throughput.

HBM4 interface doubles HBM3 ...