Stefan Mileschin

Micron announced at CES that it had started sampling of its DDR5 Registered DIMMs with select partners. The very fact that Micron started sampling of DDR5 modules indicates that its partners already have server CPUs/platforms that support DDR5 memory.

Micron expects its first-generation DDR5 products to offer ‘more than’ 1.85-times performance increase when compared to JEDEC-standard DDR4 memory. There are multiple improvements to DDR5 because in addition to data transfer rates between of up to 6400 MT/s, DDR5 also has improved functionality. Firstly, DDR5 uses two independent 32/40-bit channels per module (without/or with ECC), which improves channel utilization. Also, DDR5 has an improved command bus efficiency because the channels feature their own 7-bit Address (Add)/Command (Cmd) buses, better refresh schemes, and an increased bank group for extra performance.

What is important is that the DDR5 specification allows to design chips with capacities higher than 16 Gb and reduce supply voltage to 1.1 V and an allowable fluctuation range of 3% (i.e., at ±0.033V). So, in addition to performance, DDR5 will enable to reduce power consumption and build servers featuring higher memory capacity.

Increasing usable memory bandwidth and capacity is crucially important for next-generation server platforms that use processors with even higher number of cores.

Micron did not reveal specifications of its DDR5 RDIMMs it sent to partners or disclose when it plans to start commercial shipments of DDR5 memory. We can speculate that DDR5-enabled server platforms are several quarters away, but it is up for actual platform developers to set launch dates.

https://www.anandtech.com/show/15325...-server-makers