DDR5 memory was introduced to the market last November and the technology is still in its infancy. This week AMD and Samsung held a webinar discussing the future of DDR5 and LPDDR5X types of SDRAM as well as AMD's platforms supporting these types of memory. Among the topics discussed were AMD's Raphael desktop platform overclocking, Samsung's DDR5-6400 and LPDDR5X DRAM ICs, as well as 32Gb memory chips that will enable module makers to build 1TB modules for servers and 64GB modules for client PCs.
AMD: Ryzen 7000 'Raphael' to Make a Big Splash with Overclocking
AMD's Ryzen 7000 'Raphael' processor is certainly among the most anticipated desktop platforms in 2022. It not only brings DDR5 memory support to Ryzen, but it is also based on the next-generation Zen 4 microarchitecture that promises tangible performance improvements compared to existing Zen 3-based CPUs. But apparently there is one more thing that AMD's Raphael will offer: enhanced overclocking capabilities not possible today.
"Our first DDR5 platform for gaming is our Raphael platform and one of the awesome things about Raphael is that we are really going to try to make a big splash with overclocking" said Joseph Tao, Memory Enabling Manager at AMD, at the company's Next-Generation Memory: Introducing DDR5 DRAM webinar (at around 35:00). "I will just leave it there, but speeds that you maybe thought could not be possible, may be possible with this overclocking spec."
Considering the fact that the event was dedicated to memory and Joseph Tao is a memory enabling manager at AMD, we might assume that he was talking about enhanced memory overclocking capabilities of AMD's upcoming desktop platform.
Indeed, as CPU cores gain capabilities and execution units, and processors gain core count, they need higher memory bandwidth to ensure that there are no performance bottlenecks. Currently Intel's 12th Generation Core 'Alder Lake' processors only officially support DDR5-4800 and can already handle very high DDR5 memory data transfer rates. If the CPU is properly cooled (e.g., using liquid nitrogen) those rates can be around 8,000 MT/s or higher. We do not know what will be default memory speeds supported by AMD's Raphael CPUs, but both AMD and Samsung mentioned DDR5-5600 and DDR5-6400 speed bins in their parts of the presentation.
AMD also mentioned LPDDR5X-8500, so we can imagine that some systems based on AMD's Ryzen 6000 'Rembrandt' mobile processors with up to eight Zen 3+ cores and an RDNA 2-based integrated GPU could be equipped with such memory produced by Samsung. Yet keep in mind that officially, Rembrandt CPUs only support DDR5-5200 and LPDDR5-6400 types of memory.
But while memory overclocking might be a major feature of AMD's Raphael, keeping in mind that this processor has a thermal design power (TDP) of up to 170W, it is reasonable to assume that AMD has deliberately enhanced its overclocking capabilities to be more competitive against its rivals in enthusiast-grade desktops.
What's Next for DDR5?
Samsung has already announced its 24Gb DDR5 integrated circuits (ICs) made using its 14 nm DRAM process technology that uses extreme ultraviolet lithography on five layers to cut down die size, improve performance potential, and keep power consumption in check.
It is not completely clear when Samsung intends to initiate mass production of its 24Gb DDR5 memory devices, but this week it listed 24GB, 48GB, and 96GB memory modules based on its monolithic 24Gb ICs coming in 2022, so expect them by the end of the year at the latest. Meanwhile, Samsung already mentioned 512GB DDR5 memory modules for servers based on 16Gb memory devices in 3DS 8-Hi stacks. Given the context of the presentation, we may speculate that these modules will be fully supported by AMD's next-generation EPYC 7004-series 'Genoa' processors, so expect upcoming Genoa-powered servers with 12 DRAM channels to support at least 6TB of memory per CPU socket using one RDIMM/LRDIMM per channel (and assuming that some might get two DIMMs per channel, that maximum capacity may be increased even further).
Perhaps a more interesting question for a desktop PC enthusiast is "When will Samsung start to produce 32Gb monolithic DDR5 ICs that will enable building ultra-high-capacity memory modules for client PCs?" Unfortunately, these chips are only coming in 2024 – 2025, so we are going to be stuck with 16Gb and 24Gb-based modules for a while.
"32Gb is currently is currently under discussion and development on Samsung side," said Aaron Choi, Staff Engineer, DRAM Product Planning at Samsung. "Currently we are expecting [32Gb DRAMs coming to market commercially] in 2024 or 2025."
32Gb DDR5 memory chips may not be too crucial for client PCs since four 24GB – 48GB modules per system will provide enough memory capacity for most desktops, whereas workstation machines typically use server-grade ECC memory modules anyway. Meanwhile, 24Gb ICs will allow building memory modules of up to 768GB, which seems a rather giant size today, but this may not be good enough for servers in 2024 – 2025.
One of the reasons why it is taking Samsung a rather long time to introduce 32Gb monolithic DDR5 memory chip is probably because the company needs to adopt one or two new DRAM nodes to make 32Gb chips reasonably priced for the mass market. Meanwhile, as DRAM cells get smaller with each node, the number of single bit errors increases, which is why DDR5 adopts on-die ECC and a number of other methods to correct these errors. In any case, adopting new process technologies gets trickier with every iteration, which is why commercial availability of 32Gb DRAM chips may be years away. Meanwhile, one should keep in mind that the DDR5 specification allows building 64Gb ICs as well, so Samsung and other makers will keep scaling their nodes to take advantage of the technology.
Summary
AMD's next-generation Ryzen 6000 'Rembrandt' for notebooks and Ryzen 7000 'Raphael' for desktops are expected to get faster memory, whereas Raphael promises to offer some unexpected overclocking capabilities.
Samsung this year promises to release fast DDR5 and LPDDR5X offerings, but it remains to be seen which speed bins will be officially supported by AMD's and Intel's CPUs. Also, Samsung intends to roll out 24GB, 48GB, and 96GB DDR5 memory modules for desktops/laptops, and workstations as well as 512GB memory sticks for servers.
