DDR5 VS DDR4 - What are the advantages?

We have come to the point where the advent of each subsequent model of Intel or AMD processors will increasingly affirm the demand for the use of a newer and faster standard of DDR5 memory. In a word, DDR5 will become the dominant standard of RAM modules when it comes to new generation PC systems.

{tocify} $title={Table of Contents}

DDR5 VS DDR4 - Improvements and Differences

With the arrival of the 12th generation Intel Core processor, a new standard of memory and corresponding RAM modules - DDR5 - was promoted. It is now certain that new generations of Intel and AMD processors will use a faster standard of DDR5 memory.

DDR5 memory is designed to meet the requirements for better performance in terms of higher data transfer. While the emphasis in the presentation of the DDR4 standard was primarily on lower energy consumption for use on mobile devices, in the case of the DDR5 standard, the emphasis is on better performance.

Although they are almost the same at first glance, the biggest difference between DDR4 and DDR5 memory is at the architecture level of the module itself. The DDR5 module communicates with the memory controller via two independent 40-bit channels (32-bit + ECC) compared to DDR4 which does so via one 72-bit (64-bit + ECC).

The DDR5 DIMM module's architecture is divided into left and right sides by a comma between the pins, and each side is supplied by one of the two 32-bit data channels.  RCD or “Register Clock Driver” provides four clocks per side of the RAM module compared to two for DDR4 memory.

In addition, the improvement was achieved by increasing the amount of data during each transfer between CPU and RAM (Burst Length) from 8B (DDR4) to 16B (DDR5), which means that in one pass the memory controller can access 64B of data in DDR5 memory and this by one independent channel or half of a DDR5 DIMM.

In this way, a better effect of acceleration is enabled by the technique of so-called "intertwining" of data, ie the principle of simultaneous access to data in memory by the processor, which is crucial in the case of multi-core models.

So what doesn't the processor do in four-channel mode?

Because the memory controller in the LGA1700 series of Alder Lake models is still two-channel. This may confuse you because the hardware detection programs will report that the system has two-channel or four-channel memory configured when there are only one or two RAM modules on the board, which is not possible according to the methodology on the DDR4 platform.

The conclusion of all these data is a very certain appearance in the foreseeable future of processors with a four-channel memory controller on the desktop platform, which has so far been largely reserved for the server market, and this again coincides with the trend of CPU models nuclei.

Of course, there are even better ones with the advent of the DDR5 standard in terms of using higher-capacity memory chips, which will allow the use of more memory in a system with fewer built-in RAM modules. Then, the operating voltage was reduced to 1.1V, and the DDR5 memory voltage regulator is now located on the memory module itself, not the motherboard.

In general, it should be remembered the most important fact that the advantage of the DDR5 standard is that it achieves higher values of data transfer in communication with the CPU. This fact is especially important in the context of the release of CPUs and APU models with an increasing number of cores.

For now, the only processors that support the DDR5 memory standard are Intel Core 12000 series models in combination with Z690 and B660 chipset-based motherboards. In the middle of the year, the first AMD processors with support for DDR5 memory are expected to be released.

The mentioned Intel processors have a hybrid controller that also works with DDR4 memories. So in some cases, you will find almost identical motherboards, in the same version of the chipset, but with support for different memories - DDR4 or DDR5. Remember that the DDR5 and DDR4 standards are not compatible with each other, nor are motherboards. You cannot use DDR5 memory on DDR4 boards, or vice versa. 

The key question for us users is how much the newer DDR5 standard brings better performance. At the time of the release of the new Intel processors, the current DDR5-4800 and DDR5-5200 modules are.

As is the case when promoting DDR3 and DDR4 standards, the task of the first series of memories is to ensure a painless transition to the new standard, while performance is somehow in the background. This time it's the same strategy, so don't expect the ultimately better performance right away, but those at the level of the fastest DDR4 modules.

In some cases, performance may be at the same level or slightly worse, but this is generally the practice when promoting new standards at the outset. Maximum performance is expected a little later, with a further affirmation of the DDR5 standard and technological advances that should be crowned with the release of DDR5-6400 / 7200 and faster RAM modules.

We used an Intel Core i9-12900K processor and two Gigabyte boards with DDR5 and DDR4 RAM support based on Intel Z690 and B660 chipsets to test the findings. We tested performance in real-world apps, mostly those that require greater processing power, such as photographs, movies, and 3D modeling.

The second part of the test battery is the inevitable games and the average value of the frame rate, which affects the smooth performance of the animation during the action. Let's see how things stand in measuring the power of DDR5-4800, DDR5-5200, and on the other hand, one of the best DDR4-3600 modules at the moment.

Here we draw your attention to the fact that there are faster DDR4 modules with a higher declared clock speed of 4000 or 4400MHz, and even higher. However, they do not work in synchronous mode (1: 1) - "Gear 1", with a memory controller, which leads to a certain drop in performance in most situations because an additional frequency divider (Gear 2) is introduced.

This is done because memory controllers in the current generation of CPUs do not support working at such high memory frequencies. Therefore, in our case, we use DDR4 memory at 3600 MHz with lower latencies and "Dual Rank" organization, ie the combination that gives the best results with the current generation of Intel and AMD CPUs.

DDR5 VS DDR4 - Performance

MB 1:	Gigabyte Z690 Aorus Master DDR5
MB 2:	Gigabyte B660 Aorus Master DDR4
CPU:	Intel Core i9 12900K
RAM 1:	32GB (2x16GB) DDR4 3600 CL16 2R GSkill
RAM 2:	32GB (2x16GB) DDR5 5200 CL40 2R KingstonFURY
VGA 1:	AMD Radeon RX 6700XT
VGA 2:	Nvidia GeForce RTX 2070 Super
HDD:	Seagate Barracuda ST3000 SATA 6Gbps
SSD:	ADATA SU800 2TB
Cooler:	Gigabyte Aorus WaterForce X 360
PSU:	Cooler Master V1200 Platinum
Driver:	Intel INF Chipset 10.1.18836.8283
Driver:	AMD Adrenalin 22.2.1
Driver:	GeForce Game Ready Driver 511.65
OS:	Windows 11 Home 64-bit

Performance:

DDR5 vs DDR4 - Impressions in Work

DDR5-5200 CL40 is currently 80% more expensive, even more ie 100% for DDR5-6000 compared to DDR4-3600 CL16 of the same capacity. It is faster, especially in the part of more demanding applications, but not proportionally how much it is more expensive. However, the performance and price of the new generation of products are growing disproportionately in favor of the price, and that has been valid since the first days.
 
Another point to note is that as the number of cores increases, the Intel memory controller becomes more demanding, and this timeline can be observed historically with Intel - as the number of cores increases, so must the memory latencies. The situation is even more visible in the case of the 12th generation Core processor with a combination of energy-efficient and high-performance cores, ie heterogeneous architecture.

In the case of a top DDR4-3600 CL16-16-16 memory that runs smoothly on these parameters on an AMD Ryzen 9 model with a 16C / 32T core configuration, at the same time, the Core i9 12900K will not even wake up the system.

Only after the intervention and relaxation of the primary and secondary latency parameters on the DDR4-3600 CL17-19-19, we were able to ensure the stability of the system. So take care of this problem on the DDR4 version of the Alder Lake platform!

DDR5 VS DDR4 - Conclusion

Finally, we conclude that, as in previous cases of new memory standards, the new generation will start where the previous one left off. So DDR4 technology has reached its maximum, and it's time for a new and faster DDR5. Initially, the performance of the first DDR5 models is at the level of the fastest DDR4 and better, but with noticeably easier to achieve higher operating frequencies and less stress on the entire system. 

We can expect further progress of the DDR5 standard and accordingly "normalization" of prices to the level of DDR4 modules during and before the end of this year, and with the special interest, we will observe the progression of performance which is the main trump card of DDR5 standards.

The benefits of faster performance and overall performance of the new generation of AMD and Intel processors are undoubted, and we should not forget that it will have a special impact on the new generation of AMD APU processors that traditionally need faster memory due to better-integrated graphics core performance. When they get the RDNA 2 iGPU in the next generation, the transition to the DDR5 standard will be a complete success!