From data analytics to online gaming, an increase in demand for memory capacity has paved the way for a new generation of random access memory (RAM). Learn how DDR5 meets these challenges and provides a much-needed alternative from previous iterations.
What is DDR?
Double data rate (DDR) is a form of random access memory (RAM) used in computers manufactured after 2002. Before 2002, most computers had single data rate (SDR) memory.
What is RAM?
Random access memory is a computer chip that stores a rugged computer’s operating system (OS), application programs, and data currently in use, so they can easily be retrieved by the central processing unit (CPU).
Random access memory is short-term, as data is retained as long as the computer is on, but it leaves the RAM chip once the computer is shut off.
When the computer is rebooted, the OS and other files are reloaded onto the chip from a hard disk drive (HDD) or solid state drive (SSD).
Where are RAM chips found?
RAM chips are found on memory module chips, Single In-Line Memory Modules (SIMMs) or Dual In-Line Memory Modules (DIMMs). These modules install on the motherboard’s memory slots and store data in separate memory cells.
SIMMs are 32-bit, whereas DIMMs are 64-bit. To have the data transfer speed of one DIMM, two SIMMs need to be installed in matched pairs.
Variations of RAM
There are also variations within RAM: dynamic random access memory (DRAM) and synchronous dynamic random access memory (SDRAM).
DRAM is not synchronized with CPU clock timing, sending instructions only when received from the user interface; it uses one capacitor to store data, but that capacitor will lose data as it loses charge unless it is periodically recharged.
When the capacitor loses charge, it loses the data completely. The need to recharge is why this type of random access memory is called “dynamic.”
Since DRAM is not synchronized with any external influence, it poses a problem for organizing data as it comes in, especially with the increasing speed of processors.
In contrast, SDRAM is synchronized with CPU clock timing and sends instructions more efficiently by joining other instructions that the computer is processing, allowing the computer to receive another command before it has finished processing the previous command.
SDRAM, then, can operate at much higher speeds than DRAM, making it the most popular form of RAM offered on computers.
SDR SDRAM vs. DDR SDRAM
SDR SDRAM reads a single word of data at either the rising (start) edge of the CPU’s clock cycle or the falling (end) edge of the clock cycle, but not both, hence “single data rate.” The memory controller determines the exact time the data will be ready for processing, leaving no room for delays.
DDR SDRAM reads two words of data per clock cycle at both the rising and falling edge of the clock cycle, giving it twice as much power to transfer data than SDR SDRAM.
Variations of DDR
There are currently five generations of DDR: DDR, DDR2, DDR3, DDR4, and DDR5.
Each generation has increased memory density, lower operating voltage, and faster access, enhancing data transfer rates and processing speeds.
Here is a chart detailing the differences between the five generations of DDR:
Why the need for DDR5?
DDR5 was released on November 4, 2021.
Up until then, the most recent iteration of DDR was DDR4. DDR4 has up to 16 GB of memory capacity per RAM chip, 3.2 Gb/s data transfer rates, and 1.2V power requirements, a significant improvement over DDR3.
However, with the rise of data-intensive streaming, video conferencing, online gaming, data analytics, and AI/ML applications, DDR4 cannot keep up with the demands of modern technology.
Additionally, the business world has shifted workloads off the premises and onto the cloud, leading to a dramatic rise in hyperscale data centers.
In response to these growing challenges, DDR5 offers dramatic improvements to server performance.
Here are a few significant advantages that DDR5 has over previous generations:
- Increased memory capacity: DDR4 has 2 GB to 16 GB of memory capacity per RAM chip, whereas DDR5 has 8 GB to 64 GB of memory capacity.
- Increased bandwidth: DDR5 delivers a 50%+ increase in bandwidth over DDR4 (3.2 Gb/s), with a minimum data transfer speed of 4.8 Gb/s.
- Low voltage requirements: DDR5 has an operating voltage of 1.1V, compared to 1.2V for DDR4. This increases server performance, as using less power means less heat is given off. The more heat that is given off and not removed, the more server performance is negatively affected.
- New power architecture: DDR5 DIMMs move power management from the motherboard to the DIMM itself. These DIMMs have a 12V power management integrated circuit (PMIC) that eases signal integrity and noise challenges, offering better on-DIMM control of power supply and mitigating the margin of loss from a lower operating voltage.
- Updated channel architecture: DDR4 DIMMs have a 72-bit channel containing 64 data bits and eight ECC bits. (ECC stands for error correction code, used to detect and correct data corruption in memory.) DDR5 DIMMs have two channels, each 40 bits wide: 32 data bits with eight ECC bits. This improves memory access efficiency.
- Longer burst length: DDR4 has a burst chop of 4 bits and a burst length of 8 bits, whereas DDR5 has a burst chop of 8 bits and a burst length of 16 bits. (Burst chop means that only a certain portion of data is transferred, and burst length is the amount of data transferred.) This improves concurrency and memory efficiency.
Through higher bandwidth, increased memory capacity, low voltage requirements, and updated architecture, DDR5 meets the demands of our increasingly digitized world.
Now more than ever, large amounts of complex data need to be processed and stored at unprecedented rates, from business and entertainment to the military.
Trenton Systems strengthens aerospace and defense technologies with ruggedized, high-performance compute solutions that securely process and store mission-critical data.
This is why we equip our solutions with the latest technologies to allow increased throughput and rapid data analysis in real-time when it matters most.
Want to learn more? Get in touch with our team of experts to craft a customized solution designed to handle massive amounts of crucial data and ensure mission success.