'Near zero-cost memory expansion through recycling': Meta will reuse terabytes worth of DDR4 memory using CXL tech and avoid paying the RAM tax

Memory shortages, rising DRAM prices, and extended delivery schedules have pushed hyperscalers toward alternatives that seemed impractical only recently, but Meta has developed a way to reuse old DDR4 memory pulled from decommissioned servers rather than discarding it.

The approach allows companies to expand server memory capacity without purchasing new DRAM, a cost researchers describe as the so-called RAM tax.

This expansion is made possible through Compute Express Link technology (CXL), which connects the older DDR4 modules alongside newer DDR5 memory pools on the same machine.