DDR4 SDRAM Frequency Comparison

Computers use a form of volatile memory called random access memory (RAM), which aid in the rapid retrieval of data and applications currently in use. This helps to increase efficiency as well as data transfer rates. 

In this blog, you'll learn about the main frequencies of DDR4 (Double Data Rate Fourth Generation), how they differ, and why they are a critical component in enhancing the power of high-performance computers.

Unfamiliar with some of the terms in this blog? We got you covered! Check out our glossary of key terms for rugged computers here. 

What is DDR4?

DDR4 stands for Double Data Rate Fourth Generation. It is a form of random access memory (RAM). Specifically, SDRAM (synchronous dynamic random access memory), meaning it is synchronized with the clock speed the RAM is optimized for. 

DDR4 was released in 2014, followed by DDR5 in November of 2021. 

Benefits of DDR4

DDR4 has: 

1. More available clock speeds, lower power consumption, and reduced latency
2. No ceiling on its clock speed so far 
3. 64GB maximum capacity per memory module (most common are 16GB and 32GB)
4. 16 internal memory banks
5. 1600 to 3200 MT/s data transfer rates
6. 1.2V of electrical power required

DDR4 RAM on our TKL8255 processor board.

Applications of DDR4 

In essence, the better your RAM is, the faster and more efficient your system will be at completing any task. 

For example, if you are a software engineer, you will be able to compile code faster. If you develop CAD (computer-aided design) drawings for mechanical and electrical engineers, you will be able to develop drawings much faster. 

If you are a gamer, you would be able to access your locally stored assets much quicker, allowing for a more fluid experience.

Variations of DDR4

At a high level, the higher the frequency, the higher the data transfer rates.

DDR data transfer speed is measured in MT/s (mega transfers per second). For instance, DDR4-2666 means that it operates at a base frequency of 1333 MT/s, but because it reads data twice, it operates as if its frequency is 2666 MT/s.

The operating voltage remains that same at 1.2V, irrespective of frequency. Additionally, the chip density depends upon the manufacturer, as it relates to the storage size of the RAM. The size of the RAM influences the density of the chips.

Generally speaking, higher frequency DIMMs (Dual In-Line Memory Modules, cards on which RAM chips are stored) have a higher cost when first launched.

Over time, the price parity meets, and eventually, the lower frequency becomes more expensive due to a lack of supply as manufacturers switch to new technologies. 

Let's take a look at the different frequencies of DDR4. We'll discuss the major features of both 16GB and 32GB of each. 

DDR4-2400

Maximum data transfer rate: 2400 MT/s

Cost for 16GB (one stick): Ranging from $60 to $70

Cost for 32GB (one stick): Ranging from $100 to $110

DDR4-2666 (DDR4-2667)

DDR4-2666 is technically DDR4-2666.66, so it is sometimes written as DDR4-2667.

Maximum data transfer rate: 2666 MT/s

Cost for 16GB (one stick): Ranging from $60 to $90

Cost for 32GB (one stick): Ranging from $110 to $170

DDR4-2933

Maximum data transfer rate: 2933 MT/s

Cost for 16GB (one stick): Ranging from $75 to $100

Cost for 32GB (one stick): Ranging from $140 to $195 

DDR4-3200

Maximum data transfer rate: 3200 MT/s

Cost for 16GB (one stick): Ranging from $70 to $90

Cost for 32GB (one stick): Ranging from $85 to $140

DDR4 Tests

As you can see, the cost for one stick of DDR4 increases on two occasions: when its memory capacity increases and when its frequency increases.

People who are looking to purchase a stick of DDR4 may then ask themselves, "Well, is the extra cost worth it?"

Looking for sticks of 16GB DDR3, you will see that prices range from $40 to $170; however, prices for sticks of 16GB DDR4 are much more stable and a bit lower, ranging from $60 to $90. 

This is for two reasons. First, as a new generation of DDR becomes available, manufacturing of the previous generation slows. Second, with our currently constricted supply chain, parts and components that were scarce have now become virtually nonexistent, leading to astronomical price increases. 

A study from ResearchGate compared DDR4 to DDR3, and they were able to articulate the advantage of DDR4 over DDR3 in 6 key areas.

The study concluded that with its increased memory capacity, high speed data transfer rates, and low power consumption, DDR4 has a clear advantage over DDR3 when dealing with large, complex applications that require high bandwidth, rapid processing, and low voltage. Read the entire study here. 

Yes, DDR5 offers increased data transfer rates (up to 7200 MT/s), lower power consumption (1.1V), and higher memory capacity (512GB), but this only becomes a viable option when your system is compatible with the latest DDR generation. 

For our purposes, we are taking a look at DDR generations that our systems can support. (More on that in the next section.)

How DDR4 incorporates with our products

RAM temporarily stores data from any application, which allows said data to be retrieved faster than if the processor was trying to access the same information on a hard drive. 

The faster the RAM frequency, the faster data can be retrieved, which results in applications running faster. 

Our high-performance computing solutions support Intel® Cascade Lake CPUs, which support DDR4-2400 and DDR4-2666, Intel® Ice Lake CPUs, also known as Xeon SP CPUs, which support DDR4-2933 and DDR4-3200. 

ECC (error correction code) memory is supported across all of our platforms, but only those using the Intel® Xeon CPUs. 

We use the highest memory supported by the actual processor--or higher, clocked down.

For example, the Xeon Silver 4316 processor on our 3U BAM supports DDR4-2666, but we quote DDR4-3200 for all 3U BAM products because we want to stock a uniform speed for each product line. In this case, the DDR4-3200 would just clock down. 

How we test DDR4

Generally speaking, our current product offerings support DDR4-2666 to DDR4-3200.

We use the following applications to stress test each module and analyze them for errors. Some of the tools we use you may be familiar with, such as: 

1. Burnin
2. Memtest86
3. Stressapptest 

There are many other tools we use to stress test and measure performance. We use the Sandra Sisoft Benchmark App to capture benchmark results of the memory.

We use the Intel® Platform System Memory Rank Margin Tool to analyze the memory margining data captured from the system. It compares the data to whatever the memory module type specification is and provides a pass or fail based on whether the memory falls within the specification. 

How DDR4 differs from DDR5

The biggest differences between DDR4 and DDR5 are that DDR5 supports frequencies between 4200 and 7200 MT/s. DDR5 also has a lower operating voltage of 1.1V, meaning less power is consumed. 

DDR6 is set to come out sometime between 2024 and 2025. We will utilize DDR5 and eventually DDR6 once the processor and/or chipset supports DDR5 and/or DDR6. 

To learn more about the differences between DDR4 and DDR5, click here. 

Final thoughts

At Trenton, we seek to provide our customers with customized computing solutions that help increase efficiency, reduce latency, and minimize total cost of ownership (TOC).

DDR4 speeds up data transfer rates, ensuing the computer's CPU has instant access to all data, applications, and operating systems currently in use, so it can perform critical tasks and manage a system's overall operations effectively. 

As a member of the Intel® Early Access program, our customers have access to the latest computing technologies before they go on the market. This, in turn, allows our computers to support the latest DDR generation as soon as the processors and/or chipset are able to support it.

With decreased operating voltage, increased data transfer rates, and higher memory capacity, DDR4 increases bandwidth and boots performance at the edge in real-time, each time.