One of many world’s largest semiconductors and producers of DRAM, SK hynix, has unveiled it has working samples of a brand new technology of reminiscence modules designed for HPC and servers. Dubbed Multiplexer Mixed Ranks (MCR) DIMMs, the expertise permits high-end server DIMMs to function at a minimal knowledge charge of 8 Gbps, which is an 80% uptick in bandwidth in comparison with current DDR5 reminiscence merchandise (4.8 Gbps).
Sometimes, the most typical method to make sure larger throughput efficiency on DIMMs is by ever rising reminiscence bus (and chip) clockspeeds. This technique isn’t with out its drawbacks, nonetheless, and aiming to discover a extra complete method of doing this, SK hynix, in collaboration with each Intel and Renesas, has created the Multiplexer Mixed Rank DDR5 DIMM.
Combining Intel’s previously-unannounced MCR expertise for its server chips and Renesas’s experience in buffer expertise, SK hynix claims that their DDR5 MCR DIMM has 66% extra bandwidth than typical DDR5 DIMMs, with a formidable 8 Gbps/pin (DDR5-8000) of bandwidth. SK hynix themselves declare that the MCR DIMM will likely be ‘no less than’ 80% sooner than what’s at present on the market DDR5-wise, however it would not quantitate the way it reaches this determine.
The expertise behind the MCR DIMM is attention-grabbing, because it permits simultaneous utilization of two ranks as an alternative of 1, in essence ganging up two units/ranks of reminiscence chips in an effort to double the efficient bandwidth. Sadly, the main points past this are slim and unclear – specifically, SK hynix claims that MCR “permits transmission of 128 bytes of knowledge to CPU without delay”, however wanting on the provided DIMM photograph, there would not appear to be practically sufficient pins to help a bodily wider reminiscence bus.
Extra seemingly, SK hynix and Intel are serializing the reminiscence operations for each ranks of reminiscence inside a single DDR5 channel, permitting the 2 ranks to realize a cumulative efficient bandwidth of 8Gbps. That is supported by way of the Renesas knowledge buffer chip, which is proven to be on the DIMM in SK hynix’s pictures. Conceptually, this is not too far faraway from Load Diminished DIMMs (LRDIMMs), which employs an information buffer between the CPU and reminiscence chips as properly, although simply how far is tough to find out.
Extra curious, maybe, is that this design places an excessive amount of religion into the power of the bodily reminiscence bus and host controller (CPU) to have the ability to function at DDR5-8000 (and better) speeds. Usually the bottleneck in getting extra reminiscence bandwidth in server-grade techniques is the reminiscence bus to start with – having to function at slower speeds to accommodate extra reminiscence – so going a route that requires such a quick reminiscence bus is unquestionably a distinct strategy. In both case, the power to run DIMMs at DDR5-8000 speeds in a server can be a big boon to reminiscence bandwidth and throughput, as that is typically in brief provide with right this moment’s many-core chips.
As SK Hynix has partnered up with Intel through its MCR expertise and utilizing buffer expertise from Renesas, MCR would appear to be an Intel-exclusive expertise, no less than to begin with. As a part of SK hynix’s press launch, Intel for its half said that they “sit up for bringing this expertise to future Intel Xeon processors and supporting standardization and multigenerational growth efforts throughout the business.” Within the interim, this seems to be a expertise nonetheless beneath lively growth, and SK hynix isn’t publishing something about availability, compatibility, or pricing.
Whereas SK Hynix hasn’t gone an excessive amount of into how MCR DIMM is twice as quick as typical DDR5 reminiscence, this product is designed for the high-performance computing (HPC) and server industries, and it is unlikely we’ll see MCR DIMMs in any kind on consumer-based techniques. We count on to study extra within the not-too-distant future.
Supply: SK Hynix