SK hynix reveals DRAM development roadmap through 2031 — DDR6, GDDR8, LPDDR6, and 3D DRAM incoming

SK hynix
(Image credit: SK hynix)

SK hynix has published its DRAM roadmap at its SK AI Summit 2025. While the plans are displayed in a very general way and do not reveal important specifics, they still show the direction of DRAM technology evolution and approximate timelines of the emergence of new technologies. Naturally, since SK hynix demonstrated the roadmap at an AI event, it has a clear bias towards AI servers.

SK hynix's DRAM Roadmap.

(Image credit: SK Hynix (via @Harukaze5719))
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Anton Shilov
Contributing Writer

Anton Shilov is a contributing writer at Tom’s Hardware. Over the past couple of decades, he has covered everything from CPUs and GPUs to supercomputers and from modern process technologies and latest fab tools to high-tech industry trends.

  • usertests
    I can't wait for 3D DRAM so that 128 GB looks like the new 8 GB.

    Actually, I can wait 8 years.
    Reply
  • bit_user
    usertests said:
    I can't wait for 3D DRAM so that 128 GB looks like the new 8 GB.

    Actually, I can wait 8 years.
    I often wonder at just how it is that we're using so much RAM. I get that higher speeds require larger buffers, more threads mean more stacks, etc. Still, modern machines really do have an awful lot of RAM, and yet software does seem to gobble it up!

    My current desktop has 64 GiB (2x 32), not that I realistically think I'll ever need that much.
    Reply
  • usertests
    bit_user said:
    I often wonder at just how it is that we're using so much RAM. I get that higher speeds require larger buffers, more threads mean more stacks, etc. Still, modern machines really do have an awful lot of RAM, and yet software does seem to gobble it up!

    My current desktop has 64 GiB (2x 32), not that I realistically think I'll ever need that much.
    There's no downside to caching as much as possible, as long as you don't spill over into a page file on the SSD/HDD. Right now I have ~24 GB used, ~35 GB cached. Mostly from some browser windows. Usage may be high but we want the whole thing filled somehow.

    I think we're in a good place (as long as you bought the dip on memory). We have specialized distros (e.g. Batocera or LibreELEC) that can scale down to 1-2 GB, most people can cope with 8-16 GB on modern desktops, but you get a better experience with 32-64 GB.

    Next-gen consoles could drive PC gaming memory usage up, but only with games not supported on current-gen. It could be 5+ years until that happens. 32 GB RAM and 16 GB VRAM will likely be fine at a minimum (1080p), with 64 GB RAM and 24-36 GB VRAM for enthusiasts (4K). Adoption of AI features in gaming could drive up memory requirements of one of these pools, but it's very uncertain right now.

    Part of the promise of 3D DRAM is not just capacity increases, but $/GB decreases. If everyone ends up with large amounts of cheap RAM, LLMs and other AI models are an obvious place to waste it on. Run a 70 billion parameter model on top of everything else the desktop is doing? Maybe you want 128 GB. The sky's the limit. If you can get 512 GB for $100 in the mid-2030s, run a 300B model instead.

    If you don't use AI, 64 GB could be fine for the next 15 years. But that's a long time in the tech industry. Some of will be dead too, preemptive RIP.
    Reply
  • bit_user
    usertests said:
    I think we're in a good place (as long as you bought the dip on memory).
    Not quite. I got ECC memory and grabbed it when it was on the rise, in June of last year. I paid $295 for 64 GiB of DDR5-5600 (Kingston).

    The seller is currently out-of-stock, but now has it listed for $620. I guess I didn't do as badly as I thought, at the time?

    usertests said:
    If you can get 512 GB for $100 in the mid-2030s, run a 300B model instead.
    You will need lots of bandwidth, though. I guess they could do some sort of on-package memory with a wide interface, though. Sort of like Apple's M-series.

    I also think 3D DRAM won't reduce prices as much as you think, since each die will take a lot longer to make.

    usertests said:
    If you don't use AI, 64 GB could be fine for the next 15 years. But that's a long time in the tech industry. Some of will be dead too, preemptive RIP.
    16 GB lasted me a dozen years, in my last PC. I thought it was too much, when I bought it, and I was almost right.
    Reply
  • usertests
    bit_user said:
    I also think 3D DRAM won't reduce prices as much as you think, since each die will take a lot longer to make.
    It's like 3D NAND, but a harder problem. I am confident it will lower cost per bit just as 3D NAND did.

    Samsung has done 16 layers in the lab. They might commercialize at 16-32 layers and slowly climb from there.

    https://www.tomshardware.com/pc-components/dram/samsung-outlines-plans-for-3d-dram-which-will-come-in-the-second-half-of-the-decadehttps://www.tomshardware.com/pc-components/ram/samsung-reveals-16-layer-3d-dram-plans-with-vct-dram-as-a-stepping-stone-imw-2024-details-the-future-of-compact-higher-density-ramhttps://www.prnewswire.com/news-releases/samsung-reportedly-achieves-technical-breakthrough-stacking-3d-dram-to-16-layers-302164563.html
    Reply
  • bit_user
    abufrejoval said:
    I've pretty near always simply put the maximum RAM in all my systems since, at least when the price curve wasn't exponential per DIMM capacity. And I would sometimes add extra DIMMs later, making sure I'd be able to by choosing modules accordingly.
    I stopped filling the second DIMM slot per channel, once it started affecting the memory clock speed. I now either buy more RAM up front, or I buy less and plan for a mid-life upgrade, where I just replace the current DIMMs with new ones.

    I actually wish 2-DIMM motherboards were more common, because I'd use them if they were. However, like you, I value ECC RAM and so I must limit myself to boards which support that. 2-DIMM boards are even rarer, among that set (unless you go down to mini-ITX).

    Another argument against big RAM configurations that I've recently run across is that it increases refresh times. I need to see some real data on that.

    The main reason I have 64 GB in my desktop is due to 32 GB DIMMs being the smallest dual-rank capacity DDR5 is available in. Anandtech benchmarked single-rank vs. dual-rank DDR5 and found the dual-rank were faster, at the same clock speed & timings. Since Anandtech did application benchmarks, their results should account for any loss by longer refresh times from higher capacities, so it should still be a net win. But, I do wonder to what extent that's a measurable effect.

    The main argument for single-rank seems to be overclocking and trying to reach higher speeds or tighter timings. As I don't overclock, this seemed to be the way to get the highest performance out of my memory.

    abufrejoval said:
    With ECC RAM I feel somewhat more comfortable with all that data potentially growing stale in RAM,
    Indeed. It gives me the confidence simply to use "sleep", instead of hibernating or powering down, unless there's some reason I have to.
    Reply
  • bit_user
    abufrejoval said:
    I'd stick with quad just for the flexibility and because they won't pass any savings on to you.
    Eh, it's really not about savings, but rather that dual-DIMM motherboards have better DRAM signal quality. In the early days of LGA1700, IIRC there was some guidance about 2-slot boards reaching higher memory speeds, even if you only populated 2 slots of a 4-slot board.

    ASUS devised a new DIMM connector which supposedly mitigates the reflections caused by having an unpopulated DIMM slot. However, I read someone claiming that the precise benefits of the connector weren't accurately characterized by ASUS. Maybe it was Der8auer who discovered this?
    https://www.tomshardware.com/pc-components/ram/empty-ram-slots-can-harm-dram-performance-asus-nitropath-slots-curb-electrical-interference-gain-400-mt-s-and-are-40-percent-shorter
    abufrejoval said:
    Perhaps a Zen 6 upgrade just for kicks, not that I'd probably ever need it now.
    I got a 9600X because it was cheap and lets me play with Zen 5, while leaving lots of options. With AVX-512 being more of a thing, I'm glad to have a chance to do some tinkering. Also, since I didn't want another Intel CPU before Nova Lake, it scratched the upgrade itch for now.

    abufrejoval said:
    RAM refresh is measurable, but not noticeable: single percent less bandwidth between 'default' and 'barely still working' is what I remember.
    For me, it's mostly a just a matter of curiosity. A little bit about wanting to know the tradeoffs of going higher capacity.

    abufrejoval said:
    those caches make it much harder to still archieve any gains via coding or tuning.
    Well, the benefits that X3D CPUs have for gaming and other choice workloads stand as a testament to what one can gain with some clever, cache-aware optimizations.

    I do think it's funny when people seem to assume linked-list following will automatically blow out of cache. If you have relatively low heap fragmentation, I've found that substantial chains of list elements tend to be contiguous! You do want to take care to allocate them in one shot, rather than adding an element here, and a little while later getting another one.

    abufrejoval said:
    nobody wants to just leave free performance on the table, but I think it's not enough to actually worry or bench systematically.
    Sometimes, I like to measure things just to shine a light into what was previously a dark corner of my knowledge (and often others').

    I've gotten behind at posting some of my findings, but more of that should be forthcoming, in the next couple months.

    abufrejoval said:
    Energy consumption may perhaps be a bit more of a concern: my old Haswell/Broadwell E5-2696 Xeons consistently reported much more Wattage being consumed by those 128GB in eight DDR4-2133 ECC DRAM DIMMs than the 18/22 Xeon cores. Not that both ever consumed as much as the GPUs it was carrying. It never really gets hot, but its far from Mini-ITX idle power, while compute performance on say a Hawk-Point APU is actually better at much lower idle. Some progress was actually made between 14 (Intel) and 6 nm (TSMC).
    FWIW, I replaced a Sandybridge i7-2600K with an Alder Lake i5-12600 (4-core -> 6-core). Both using iGPU for graphics, with one SSD and an optical drive. Idle power on the new system is maybe 20% lower. The old system had 2x 8 GB DDR3-1600 DIMMs, while the new one uses 2x 32 GB DDR5-5600.

    The biggest efficiency improvement seems to be in the area of the iGPU. Running the same OpenGL benchmark, the self-reported iGPU power is like half as much on the new system, even though its iGPU is an order of magnitude higher performance!
    Reply
  • thestryker
    Put me in the "I really wish there were more 1DPC boards" camp. When I was building my current system I really wanted a 2 DIMM board, but the price premium over what I got was $100/200/220 for ASRock/MSI/Asus and Gigabyte hadn't released theirs. The only other options tend to be entry level boards with nothing in between.

    When I was looking to get higher speed memory I almost went with a 32GB kit instead of 48GB due to default refresh timings. Most of the 32GB kits were 1.45V instead of 1.4V so I figured I could go to the minor effort of manually adjusting subtimings.

    I would really like to see a test of single rank and dual rank modules with 16/24/32Gb IC density at the same speed. I know 16Gb refresh timings are lower than 24Gb so it's reasonable to assume the same would be true with 32Gb. I was really hoping to test a dual rank kit on my system, but none of them ship at both high clock speed and low latency. With the way the market is looking now I don't see that really changing as I'd imagine the enterprise market is eating up most of the new IC designs.
    Reply
  • thestryker
    Had some more thoughts which were more on topic:

    I'm hoping that forthcoming workstation platforms will have MRDIMM support so we can get an idea as to the full performance characteristics. If GNR in workstation form is overclockable and supports MRDIMMs this could shed a big light on Intel's EUV process clock characteristics as well. I don't really expect these to make their way to consumer products since they're registered and that's always been a barrier for client parts, but one can dream. Now that client memory needs a clock driver I think an argument can be made for everything being registered, but nobody wants to eat the cost for extra memory IC per DIMM (a much bigger problem currently thanks AI).

    The fact that DDR5 isn't going anywhere any time soon isn't very surprising. The issues with 2DPC certainly aren't going away with a new technology and DDR5 can clock significantly higher than any official JEDEC specs that have been released. SK Hynix has started rolling out new IC in 16Gb, 24Gb and 32Gb sizes (this may be their first 32Gb as Micron already went to market with theirs) and Micron has some DDR5-7200 in validation (this is notable since none of their memory has even reached this speed as XMP/EXPO kits as far as I'm aware). Unfortunately Samsung is seemingly MIA from the new DDR5 game, but this may be partly due to all of their other fabrication issues and having resolve some HBM issues.

    For years now I've been in a default state of "get back to me when it's productized" regarding anything that's touted to replace or directly augment DRAM. I do think there's definitely a compute problem where DRAM and NAND are always going to be what they are and there's room for a bridge between the two. I'd of course make the argument that Intel already brought that to the market, but fumbled the execution horribly. There are always plenty of possibilities to bridge the gap, but nothing so far has stuck.
    Reply
  • usertests
    abufrejoval said:
    It shows 80GB used... without a single VM running.

    And no, it's not a memory leak or a huge application: Windows has just started to behave a lot like Linux or Solaris: they'll keep anything they come across in cache, because that is just a tad better than leaving it unused in case somebody might want that data again.
    When someone (not you) says "used", they should specify if that's with or without cache. Here I am at ~28 GB used, ~35 GB cached.

    This is a good thing.
    bit_user said:
    I actually wish 2-DIMM motherboards were more common, because I'd use them if they were. However, like you, I value ECC RAM and so I must limit myself to boards which support that. 2-DIMM boards are even rarer, among that set (unless you go down to mini-ITX).
    You know where it's common? OEM PCs, like the clearance Aspire XC I'm using (upgraded from single-channel 8 GB to dual-channel 64 GB, lol), or the 1-liter PCs.

    Today's clearance "e-waste" is ultra powerful and useful. So are the systems from 10 years ago.
    abufrejoval said:
    Actually I had already forgotten I had to do the same on my Ryzen 7950X3D with DDR5... It's only 96GB in with dual 48GB modules, because with four DIMMs speeds were atrocious enough to actually notice. Dual 64GB was exponential in cost so it got stuck with 96, which is a good compromise.
    64 GB UDIMMs must have been extremely new when you built, since they debuted around March 2025. Or were you looking at server-grade memory?

    Seems they are going for around $700 per 2x64GB kit right now. But sometime within the next 5 years they could be close to $1/GB.
    Reply