High bandwidth memory (HBM) is DRAM built as a tower. Eight, twelve or sixteen memory dies sit on top of a logic base die, wired together vertically, and the whole stack is placed a few millimetres from a GPU or AI accelerator inside the same package. The reason is bandwidth. One HBM4 stack moves at least 2 terabytes per second, more than three times what a 12-channel DDR5-6400 server socket manages (about 614 GB/s).

Hybrid bonding joins two chips by pressing their polished faces together so that copper pads on one fuse directly with copper pads on the other. There is no solder, no bump and no gap. The name comes from the two bonds made at once: the insulating surfaces stick to each other, and the embedded copper pads weld into continuous metal. Because nothing sits between the dies, connections can be packed far closer together than solder allows, and stacks get thinner and cooler.

A laptop review is not usually a memory-cycle datapoint. This one is. The Framework Laptop 13 Pro drew strong marks for performance, build quality, and keyboard, and was marked down on a single dimension — it is expensive, and the review attributes that expense to high RAM prices. That sentence is the cleanest publicly visible evidence to date that high-bandwidth memory wafer allocation has stopped being a datacenter accounting problem and started setting bills of materials on consumer hardware.