DDR4 vs DDR5 Server Memory in 2026: Where the Money Goes

18 Oct 2026 · DDR4, DDR5, server memory, buying guide

What actually changed

DDR5 RDIMMs are now standard on new platforms (Sapphire Rapids, Genoa, Bergamo): 4800–6400 MT/s, 1.1 V, with the PMIC moved onto the module. DDR4 RDIMMs (2133–3200 MT/s, 1.2 V) are still the cheaper per-GB path for capacity rebuilds on Cascade Lake, Rome and Milan.

Three numbers that decide the bill

1. Cost per GB, not cost per module. A DDR4 64GB 2Rx4 module usually wins on dollars per gigabyte. A DDR5 64GB module wins on bandwidth per watt.
2. Slots times ranks. For the same capacity, 2Rx4 fills fewer slots than 2Rx8: fewer modules, less power draw, higher price each.
3. Platform lock-in. DDR5 does not fit DDR4 slots, and DDR4 does not fit DDR5. Buying DDR4 today extends the life of DDR4 servers only.

When DDR4 still makes sense

If the fleet is Cascade Lake, Rome or Milan and the job is adding capacity, DDR4-3200 2Rx4 is normally the lowest cost per GB. If platforms are being refreshed, DDR5 is the only forward path and DDR4 stock should be treated as a runway, not an investment.

What we stock

The current list covers DDR3, DDR4 and DDR5 RDIMM and LRDIMM plus HBM and VRAM chips: 112 SKUs, EXW China, MOQ 1 pc, dispatched within 2 working days. Prices track the spot market, so confirm before a bulk order.

See the current stock list

Continue with the full buying guide: rdimm-vs-lrdimm.