AMD and JEDEC promote DDR5 MRDIMM memory standard: Speeds Up To 17,600 MT/s

Recently at Memcom 2023, AMD announced its collaboration with JEDEC to promote the DDR5 MRDIMM memory standard. Compared to the existing DDR5 DIMM, bandwidth is set to experience a significant leap, targeting a speed of 17,600 MT/s.

According to TomsHardware, MRDIMM, or Multi-Ranked Buffered DIMMs, combines two DDR5 DIMM modules to provide double the data transfer rate. It necessitates a specialized data buffer to merge and convert them into a single QDR. For instance, if the DDR5 DIMM rate is 4,800 MT/s, the resulting output will reach 9,600 MT/s.

Image credit: Robert Hormuth/LinkedIn

The first-generation DDR5 MRDIMM aims for a speed of 8,800 MT/s, gradually increasing in subsequent generations. The second generation will achieve 12,800 MT/s, while the third generation will elevate to 17,600 MT/s. However, it is unlikely that third-generation DDR5 MRDIMM will materialize before 2030, as it is a long-term objective.

Currently, Intel is partnering with SK Hynix and Rambus to develop MCRDIMM, or Multiplexer Combined Ranks DIMMs, a solution similar to MRDIMM. AMD has prepared a comparable name, called HBDIMM, though some differences exist between the two. Due to the temporary absence of public information, a direct comparison between these memory types remains unattainable.

SK Hynix states that the first-generation MCRDIMM speed surpasses 8,000 MT/s, presumably on par with the first-generation MRDIMM. Intel has recently demonstrated the combination of MCRDIMM with its next-generation Granite Rapids, achieving a speed of 8,800 MT/s and a memory bandwidth of 1.5 TB/s in a dual-socket system.

The DDR5 MRDIMM roadmap remains nebulous, and the timeline for the first-generation product’s emergence is unclear. AMD’s next-generation Zen 5-based EPYC server processor (codenamed Turin) is set to launch in 2024, and it is reasonably expected to support DDR5 MRDIMM. However, official confirmation has yet to be provided.