The JEDEC association has not yet officially published the specification for the next generation of DDR5 RAM (dynamic random access memory, DRAM). But the absence of a formal document does not prevent DRAM manufacturers and developers of various systems on a chip (system-on-chip, SoC) from preparing for its launch. Last week, Cadence, a developer of hardware and software for chip design, shared its information regarding the introduction of DDR5 to the market and its further development.
DDR5 platforms: more than 12 in development
The mass character of any type of memory is determined by the mass character of platforms with its support, and DDR5 is no exception. In the case of DDR5, we know for sure that AMD EPYC Genoa processors, as well as Intel Xeon Scalable processors of the Sapphire Rapids generation, will support it when they are released in late 2021 or early 2022. Cadence, which already offers a DDR5 controller and a DDR5 physical interface (PHY) to chip designers for licensing, says there are more than a dozen next-generation memory capable SoCs in development. Some of these systems-on-a-chip will appear earlier, some later, but at this stage it is obvious that interest in the new technology is very high.
Cadence is confident that the company's DDR5 controller and PHY DDR5 are fully compliant with the upcoming JEDEC version 1.0 specification, so SoCs that use Cadence technologies will be compatible with DDR5 memory modules that will appear later.
“Close participation in JEDEC working groups is an advantage. We get an idea of how the standard will evolve. We are a supplier of controllers and PHYs and can anticipate any potential changes along the way to ultimate standardization. In the early days of standardization, we were able to take standard elements under development and work with our partners to get a working controller prototype and PHY. As we move towards the publication of the standard, we have more evidence that our intellectual property (IP) package will support DDR5 compliant devices,” said Marc Greenberg, director of marketing for DRAM IP at cadence.
Antre: 16Gb DDR5-4800 chips
The transition to DDR5 presents a major challenge for memory manufacturers, as the new type of DRAM must simultaneously increase chip capacity, increase data transfer rates, increase effective performance (per clock and per channel), and at the same time reduce power consumption. In addition, DDR5 is expected to make it easier to combine multiple DRAM devices in a single package, and this will significantly increase the capacity of memory modules compared to what the industry uses today.
Micron and SK Hynix have already announced the supply of prototype memory modules based on 16Gb DDR5 chips to their partners. Samsung, the world's largest DRAM manufacturer, has not officially confirmed the start of prototype shipments, but from its announcements at the ISSCC 2019 conference, we know that the company is working with 16 Gb chips and DDR5 modules (however, this does not mean that 8 Gb chips DDR5 will not). In any case, it looks like DDR5 memory will be available from all three major DRAM manufacturers as soon as the respective platforms hit the market.
Cadence is confident that the first DDR5 chips will have 16Gb capacity and 4800 MegaTransfers per second (MT/s) transfer rates. This was indirectly confirmed by the demonstration of the SK Hynix DDR5-4800 module at CES 2020, coupled with the announcement of the start of sampling (the process of sending product prototypes to partners). From DDR5-4800, the new generation of memory will develop in two directions: capacity and performance.
General vectors for the development of DDR5, according to Cadence's expectations:
- The capacity of a single chip will start at 16 Gb, then increase to 24 Gb (wait for 24 Gb or 48 Gb memory modules), and then up to 32 Gb.
In terms of performance, Cadence expects DDR5 data rates to go from 4800 MT/s to 5200 MT/s in 12-18 months after the launch of DDR4-4800, and then to 5600 MT/s in another 12-18 months. , so DDR5 performance improvements on servers will occur at a fairly regular pace.
For client PCs, a lot will depend on microprocessor memory controllers and memory vendors, but enthusiast DIMMs will certainly have better specs than those used in servers.
In the server market, with 16Gb chips, DDR5 internal architecture optimizations, new server architectures, and the use of RDIMMs instead of LRDIMMs, single-socket systems with 5GB DDR256 modules will see significant performance gains both in terms of throughput capabilities, and in terms of data access delays (compared to modern LRDIMMs).
Cadence says the technology improvements to DDR5 will increase actual memory bandwidth by 36% over DDR4 even at 3200 MT/s. However, when DDR5 runs at design speeds of around 4800 MT/s, actual throughput will be 87% higher than DDR4-3200 anyway. However, one of the key features of DDR5 will also be the ability to increase the density of a monolithic memory chip beyond 16 Gbps.
DDR5 already this year?
As noted above, AMD Genoa and Intel Sapphire Rapids should appear no earlier than the end of 2021, and more likely the beginning of 2022. Nevertheless, Mr. Greenberg from Cadence is confident in the optimistic scenario.
Memory manufacturers are aiming to start mass shipping new types of DRAM before the platforms become available. Meanwhile, deliveries a year before AMD Genoa and Intel Sapphire Rapids hit the market seem a little premature. But the appearance of DDR5 trials has several reasonable explanations: AMD and Intel processors supporting DDR5 are closer than processor companies tell us, or there are other SoCs with DDR5 support that are entering the market.
In any case, if the DDR5 specification is at the final draft stage, major DRAM manufacturers can start mass production even without a published standard. Theoretically, SoC developers could also start sending their developments to production already at this stage. Meanwhile, it is hard to imagine that DDR5 will capture any significant market share in 2020-2021. without support from major processor vendors.
Source: 3dnews.ru