As the successor of DDR4 memory and the “natural” good partner of CPU in the future, it took quite a long time for ddr5 to launch the sample at the beginning of last year and finally to formally determine the standard by JEDEC (solid state storage association). Is it worth the long wait? What’s the difference between DDR4 and its competitors? Let’s talk about it today.
If we want to talk about the development of ddr5, we have to go back to 2016. After the overall situation of DDR4 has been decided, the major memory granule manufacturers begin to consider the next generation of products. The frequency was doubled according to the mainstream memory at that time, that is, the equivalent frequency of 3.2ghz (2 times of DDR3 1600), and the maximum mainstream frequency was 6.4ghz (2 times of DDR4 3200).
Its frequency doubling method is the same as DDR1, 2, 3 and 4 before. It uses the different level in each clock cycle to trigger “action”, so that it can obtain several times of the equivalent operating frequency while maintaining the basic frequency. This progressive development has better compatibility, which is one of the main reasons why ddr5 becomes the next generation standard.
Of course, in order to achieve such a high speed and ensure the stability of high-speed operation, ddr5 also adds some new modules, circuits and algorithms, such as phase rotator, injection locked oscillator, etc. in addition, better chip manufacturing process will be adopted.
In the recently released ddr5 standard, there are some details that have been ignored before. For example, the doubling of the number of banks actually increases the bit width, parallel transmission capacity and capacity expansion capacity of the memory module itself, and the bandwidth under the same frequency is significantly improved. In addition, the frequency is finally upgraded to 4.8ghz-8.4ghz based on the current mainstream DDR4 memory. In the future, there is no problem in doubling the computer’s memory bandwidth, and the highest frequency can reach more than three times of the current memory bandwidth.
The determination of some details is also reassuring. For example, the voltage of DDR4 memory is reduced from 1.2V (in fact, 1.35v is commonly used in high-frequency memory) to 1.1V, which can better control the power consumption. At present, almost all published ddr5 memory has no heat sink, indicating that its power consumption and heating performance are really good. In addition, in order to ensure stability, the standard also requires a higher voltage tolerance, and we don’t have to worry about whether it will be damaged if it uses such a low voltage.
Of course, Xiaobian doesn’t mean that ddr5’s performance is invincible. For example, hbm2e’s bandwidth in recent mass production far exceeds it. Aoteng’s memory is slower, but it can retain all data after restarting the computer. Game console uses gddr6 video memory as its main memory, and the effect is good. However, there are still many problems in the cost and architecture of these memories, which have little impact on the consumer market. Therefore, the next generation of consumer memory is ddr5, which should be stable.
As for performance, the previous push mentioned that CPUs with “standard frequency” settings, supported by higher bandwidth memory, will have obvious performance improvement, not to mention the future CPU optimized for ddr5 memory. The only drawback is that this standard is really late. It is estimated that CPUs designed or modified according to it will have to wait at least another generation. In addition, commercial platforms will compete for production first, so it is estimated that ddr5 will not be available until 2022.