Micron samples faster DRAM with DDR5 DIMMs

Micron today became the first supplier to sample DDR5 memory modules. They use 1z nm technology and should speed memory access for multi-core CPUs.

DDR5 memory is expected to become the standard memory for most computing devices. Micron claims it will help servers cope with greater workloads by delivering 85 per cent-plus better memory performance than DDR4.

Tom Eby, SVP of the compute and networking business unit at Micron, issued a quote: “The key to enabling these workloads is higher-performance, denser, higher-quality memory. Micron’s sampling of DDR5 RDIMMs represents a significant milestone, bringing the industry one step closer to unlocking the value in next-generation data-centric applications.”

Double data rate

The JEDEC standards authority has specified DDR5 (Double Data Rate 5), the fifth DRAM generation, to have double the bandwidth and capacity of DDR4.

The technology is called double data rate because it transfers two messages per clock tick (MT/sec). Double data rate DRAM that runs at 1066.6MHz can transfer 2133 MT/sec.

Measured this way, DDR4 data rates range from 1600 to 3200 MT/sec. DDR5 increases this to 3200-6400 MT/sec.

At 3200 MT/sec, DDR4 memory provides 134.3 GB/sec effective bandwidth whereas DDR5 3200 will deliver 182.5 GB/sec effective bandwidth. This is a 1.36x speed up. The claimed >1.85x speed increase comes with a 4800 MT/sec rate product, as the chart below shows:

Micron’s one zee

Micron’s 1x memory nodes have 17nm cell sizes; 1y is unspecified but smaller and 1z is smaller again. Its three node shrinks after 1z are known as 1α, 1β and 1γ. The smaller the node the higher the chip density.

Micron sample chips are RDIMM format which are more reliable than ordinary DIMMs because the control signals are buffered in a register.

SK hynix will begin mass-production of its 1Znm DRAM in 2020. ITs 1Z measurement may well be different from that of Micron’s 1z.

Check out a Micron White Paper to dig deeper into its DDR5 DRAM tech.