Just like all major makers of DRAM, SK Hynix produced its first DDR5 memory chips a couple of years ago and has been experimenting with the technology since then. To that end, it is not surprising that the company displayed its DDR5 RDIMM at CES 2020, which implies that development is proceeding as planned.
At the trade show, SK Hynix demonstrated its 64 GB DDR5 RDIMM with ECC rated for a 4800 MT/sec/pin data transfer rate. The module marked as HMCA8GR8MJR4C-EB carries 20 memory chips marked as H5CNAG4NMJ as well as IDT’s P8900-Z2 register clock driver (RCD). The memory devices are marked differently than the ones SK Hynix used for 16 GB RDIMM back in late 2018, though we do not know the difference.
The DDR5 RDIMMS feature 288 pins on a slightly curved edge connector (to reduce the insertion force on every pin), just like DDR4 modules, yet its layout and design are a bit different when compared to DDR4 to prevent installment of DDR5 modules into DDR4 slots and vice versa.
It is unknown whether SK Hynix has already started to sample its DDR5 RDIMMs with developers of server platforms and servers, but it is obvious that all DRAM makers are aligning their DDR5 production schedules with CPU designers and other companies.
At present, it is unclear when exactly the first DDR5 platforms are set to hit the market, but a good guess would be 2021. One of the first platforms to confirm support for DDR5 memory has been Intel's Xeon Sapphire Rapids, set for deployment in the Aurora Supercomputer. AMD support for DDR5 is unknown so far.
https://www.anandtech.com/show/15375...ddr54800-rdimm
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14th January 2020, 08:11
Here's Some DDR5-4800: Hands-On First Look at Next Gen DRAM 
