Better Dedicated Server Memory: DDR4 RAM vs. DDR3

June 2015

dedicated servers ram - DDR4

Introduced to the market in 2014, DDR4 RAM for dedicated servers has a number of advantages over its predecessor DDR3 RAM. DDR4 SDRAM stands for double data rate fourth generation synchronous dynamic random-access memory. Despite the long name, it is the latest and greatest in memory available for our dedicated servers. Development of DDR4 began in 2005, and it introduces power consumption decreases and bandwidth improvements to ensure complete server efficiency. We will outline advantages of upgrading to DDR4 RAM.

Dedicated Server Performance & Bandwidth

One of the biggest advantages is the increased data transfer rate with DDR4 vs. DDR3. The older tech starts at 800 MT/s (millions of transfers per second) and tops out at 2133 MT/s, whereas DDR4 starts at 2133 MT/s. This increased speed means a corresponding increase in bandwidth, thus improving performance. This of course does lead to increased latency due to the higher clock speed, but the difference is negligible. The real performance improvements will be seen by dedicated servers that require greater RAM bandwidth. This is where DDR4 really shines.

Bandwidth Comparison

The below chart (source: anandtech.com) gives a great overview of the bandwidth increases seen by upgrading to DDR4.

Bus Clock	Internal Rate	Prefetch	Transfer Rate	Channel Bandwidth
DDR	100-200 MHz	100-200 MHz	2n	0.20-0.40 GT/s
DDR2	200-533 MHz	100-266 MHz	4n	0.40-1.06 GT/s
DDR3	400-1066 MHz	100-266 MHz	8n	0.80-2.13 GT/s
DDR4	1066-2133 MHz	100-266 MHz	8n	2.13-4.26 GT/s

Power Consumption

DDR4 RAM operates at 1.2V as compared to DDR3, which operates at 1.5V. This may not seem like a lot, but when you multiply this across thousands of servers, the average of 15W savings per server is definitely a big deal. This is a 20% power reduction over DDR3. Any dedicated server owner wanting to reduce their carbon footprint and reduce power consumption should consider this a great step in the right direction. This decreased voltage in DDR4 memory also leads to less heat generated by the server, meaning longer server life and less energy needed to cool the server as well. This change will have a large impact on mobile devices that begin to utilize DDR4 in the coming years. The decreased voltage will mean longer battery life for mobile phones and laptops.

Supported Servers

Currently, we have several servers at ReliableSite that support DDR4. These models are the Intel Xeon E5 V3 and Intel Xeon D. We expect future models like the Xeon E3 V5 to support DDR4 as well. Links to order supported servers can be found below: