DDR5 MRDIMM and LPDDR6 CAMM options may play an important role in the future.
Reflecting on the rise of AI, JEDEC is already working on the standardization of memories for the server market and clients designed for new needs. The JESD318 CAMM2 further development is coming to the latter area, which provides the possibility of LPDDR6 standard memory capable of a speed of at least 14.4 GT/s for the CAMM format. Such a module is planned to work with 24-bit subchannels and 48-bit channels.
A standard, high-speed version of the MRDIMM is being prepared for the server market, which uses DDR5 memories, and the effective speed will be 8.8 GT/s.
By the way, the MRDIMM itself is not really new, several manufacturers have already presented their prototypes, sometimes under the name MCR DIMM, and the essence is that the memory module uses two ranks so that the data buffer built on the module manages them simultaneously. This means that the two ranks transmit 64 bytes of data to the data buffer per cycle, i.e. a total of 128 bytes. This operation is invisible on the processor’s side, since the access essentially targets the extra data buffer, which stores the currently important data and forwards it to the processor with 64 bytes per cycle as needed.
In order to facilitate the transition to MRDIMM, JEDEC uses the existing LRDIMM ecosystem, and essentially the capacity and speed of the memory modules intended for the server will be increased in such a way that the packaging of DRAM chips would have to be modified. This allows manufacturers to use the same memory chips for existing modules as well as for new ones.
Source: prohardver.hu
