The 13th generation PowerEdge server family, based on the Intel E5-2600 v3 family CPU, implements the new DDR4 system memory standard which offers advantages over 12G's DDR3 including faster speeds, increased bandwidth, higher density, more energy efficient and with improved reliability.

 Let's consider each of these advantages in more detail.

- Faster speeds: By 14% when populated at 1 and 2 DIMM per channel (DPC). This goes up to 40% at 3DPC. These frequencies will to scale up to 2400 MHz in 2015.

- Increased Bandwidth: That speed increase translates to higher throughput as this comparison using the popular STREAM memory bandwidth benchmark illustrates.

 To put actual quantities to these relative improvement percentages; here are measurements from PowerEdge models R630 and R620. Note these are with just a single processor installed. Total system bandwidth of a 13G launch platform has been measured at 120 GB/s!

 - Higher Density: DDR4 offers scalability for the future: Individual DIMM densities start at 4GB and go up thru 32GB today with 64GB availability in 2015. Imagine the 1U model with 1.5 TB or the 4U model with 6 TB for virtualization and big data applications. Here's how the mainstream DIMM size has been trending.

  - More efficient: With energy efficiency increasingly important with each new CPU/GPU architecture, regulatory certification requirements and server buying decisions; DDR4 enables just that as you can see here.

And so DDR4 system deployment will save not just electricity, but data center provisioning like backup power, cooling and physical space.

Even in a memory-rich PowerEdge T630 configuration running the especially intensive Linpack benchmark, we found that its DDR4 memory subsystem now accounted for just 4% of the overall system input power requirement. And again, this was while that memory sustained 16% better throughput than DDR3 could in the comparably configured 12G T620.

 - More reliable: DDR4 implements real-time write error detection/correction to its internal command and address busses, not just the data bus that DDR3 was limited to. DDR4 also adds built-in thermal monitoring with the provision to adjust its access timings should a temperature excursion occur.

Thanks for reading. In a future installment I'll talk on other 13G PowerEdge memory performance aspects including: access latency, Performance vs Lock Step memory configuration, RDIMM vs LRDIMM, Node Interleaving (NUMA vs UMA), 1x vs 2x refresh and CPU Snoop mode sensitivity.