89 pointsby akyuua day ago8 comments
  • magicalhippoa day ago
    Will be interesting to see how long this RAM insanity will last. If it doesn't calm down before Zen 6 releases, people like me on older platforms might just have to skip Zen 6 entirely and wait for the AM6 platform.
    • FootballMusea day ago
      • rafaelmna day ago
        Can they double the memory lanes without switching socket ? If not I feel like PC is going to fall behind even further compared to Apple chips. Having ram on chip sucks for repairability but 500gb/s main ram bandwidth is insane.

        They stumbled into the right direction with strix halo but I have a feeling they won't recognize the win/follow up.

        • zamadatixa day ago
          The "insane" RAM bandwidth makes sense with Apple M chips and Strix Halo because it's actually "crap" VRAM bandwidth for the GPU. What makes those nice is the quantity of memory the GPU has (even though its slow), not that the CPU has tons of RAM bandwidth.

          When you go to the desktop it becomes harder to justify including beefed up memory controllers just for the CPU vs putting that towards beefing some other part of the CPU up that has more of an impact in cost or performance.

        • dogma1138a day ago
          Not easily, and you will need a new motherboard anyhow because each of the 2 slots you can have per lane are wired in tandem.
        • Numerlora day ago
          The socket io locks in the amount of memory channels. Some pins could be repurposed but that's pretty much a new socket anyway.

          They could in theory do on package dram as faster first level memory, but I doubt we'll see that anytime soon on desktop and it probably wouldn't fit under the heat spreader

          • dogma113819 hours ago
            They already do the latter with X3D.

            You won’t be able to add RAM to the die itself there no room on the interposer really.

        • nutjob2a day ago
          > Can they double the memory lanes without switching socket?

          Sure. Keep the DIMM sockets and add HBM to the CPU package.

          Actually probably the best possible architecture. You can choose to have both or only one, backward compatible and future proof.

          Yes, it adds another level to the memory hierarchy but that can be fine tuned.

          • dogma113819 hours ago
            It’s really not that simple, the unpopulated memory slots will cause havoc with signal integrity 4 slot boards already suffer from this.

            You are also overestimating how much room there is on the interposer.

            As someone with a 9950x3d with direct die cooling setup I can tell you there is no room.

      • tpurvesa day ago
        So Zen 6/7 will have a core design and a CCD design. But like past gens, these will be packaged into different products with different sockets and packages (everything from monolithic APUs to sprawling multi-chiplet Server cpus).

        So to say that Zen 6/7 supports AM5 on desktop, doesn't necessarily exclude that Zen 6/7 product family in general doesn't support other new/interesting sockets on desktop (or mobile) also. Maybe products for AM6 and AM5 from the same zen family.

        Medusa Halo and the Zen7 based 'Grimlock Halo' version might be the interesting ones to watch (if you like efficient Apple-stlyle big APUs with all the memory bandwidth)

    • Pet_Anta day ago
      Higher DRAM prices might mean that there is less demand from new system builders mean depressed prices so it might be more tempting to upgrade your existing AM5 CPU to Zen 6
      • Ritewuta day ago
        I would figure the opposite. There are plenty of people like me staying on AM4 because of the RAM price increases. I will probably skip AM5 entirely.
        • 0cf8612b2e1ea day ago
          I am a hypocrite, but there is really not that much need to upgrade CPUs anymore. Even a ten year old chip seems completely adequate for day to day use. I played with a N100 recently and those things are incredibly capable.

          (Ignore my AM5 workstation with 192GB RAM in the corner)

          • bikelanga day ago
            I rocked my Haswell i5 until last year when I built a brand new machine around the 9800x3d. Along the way I upgraded it from 8gb of ram to 32gb, got a gen 1 pcie3 NVME, and went through successive hand-me-down GPUs starting from a GeForce 770 to the RTX 2070 it has now.

            In fact my wife is still rocking that machine - although her gaming needs are much less equipment intense than mine. After a small refurb I gave it (new case, new air cooler, new PSU) - I expect it to last another 5 years for her.

            • ocdtrekkiea day ago
              I rode out an i7-4790K until this year... replaced solely because of Windows 10 support ending. But it's a solid chip.

              My new one is a 9700X. Didn't feel the need to spring for higher power budget for a marginal gaming performance bump. But I suppose that also means it's much more practical for me to jump to a newer CPU later.

              • snvzz12 hours ago
                Similarly, went from i7-4790K with 32GB RAM to 9800x3d with 96GB ECC RAM.

                It's faster than the prior machine, but it sure does not feel like it does things the previous one didn't

                • ocdtrekkiean hour ago
                  Heh I also only sprung for 32 GB of RAM this time, which is still double my 4790K's 16 GB. But I don't use Chrome so RAM doesn't get used that heavily. ;)

                  I think it's very telling so many people upgrading now are coming from Haswell chips, they are a legendary chip generation, and arguably the last time anyone needed a CPU upgrade short of operating system support or warranty concerns.

          • pjjpo13 hours ago
            Had been running a coffee lake refresh 4 core for several years and as interested as I was in new platforms, especially AM5, the work of replacing motherboard never felt worth it. Now with the ram wars heating up, I just committed to that by picking up a used top-end 8 core coffee lake for $50 to cut a few seconds off my vulkan shader compiles with minimal replacement effort.
          • johnbellonea day ago
            I really wish I would've bought 192G when it was less than a few thousand dollars!
            • 0cf8612b2e1ea day ago
              Heh. It was a luxury purchase at the start of the year when I was only worried about tariffs. Wanted to lock in a new build good for years. Every once in a while I have a machine learning project that needs over 100GB and so it is nice not to have to overthink things. Honestly, I’m kicking myself I did not go all the way with 256GB.
              • ciupicri20 hours ago
                I assume you're using 4 modules of memory, so the while the capacity is high, the bandwidth is low.
          • Sohcahtoa82a day ago
            Depends wildly on what you're doing.

            I'm a gamer, often playing games that need a BEEFY CPU, like MS Flight Simulator. My upgrade from an i9-9900K to a Ryzen 9800X3D was noticeable.

          • imtringueda day ago
            You say that, but DDR6 will double the memory bandwidth over DDR5. This means modern systems will go beyond 200GB/s memory bandwidth just for the CPU alone.
            • kvemkona day ago
              > DDR6 will double the memory bandwidth over DDR5

              Considering PC desktops. DDR4 is 3200 MT/s max JEDEC. DDR5 is available on AMD since 3 years and is 5600. DDR6 specification is almost finished. It looks like DDR5 will double performance just right before new DDR6 DIMMs appear. Thus I'd expect DDR6 to double the bandwidth just as late when the new memory standard arrives.

              • yetihehea day ago
                > DDR5 is available on AMD since 3 years and is 5600

                Strange, I bought 64GB DDR5 6400MHz last year and apparently my motherboard can handle up to 7200MHz (or more with overclocking).

                • wtallis21 hours ago
                  AMD's CPUs don't support more than 5600 MT/s without overclocking; they're still using the same IO die from Zen 4, so their memory controller is pretty outdated. Zen 6 should introduce a new IO die with a better memory controller, but for now 6000 MT/s is the fastest reasonable memory overclock for AMD desktops.

                  Intel's desktop CPUs from last year support up to 5600 MT/s with regular DDR5 DIMMs, or 6400 MT/s for CUDIMMs. Speeds higher than this are achievable, but are overclocking.

                  If your memory modules are rated for 6400 MT/s, they are most likely advertising the speed when using an Intel XMP or AMD EXPO profile to overclock the memory (and the CPU's memory controller). The JEDEC standard profile likely is no faster than 5600 MT/s. It's also possible that you bought last year a kit of CUDIMMs rated for 6400 MT/s without overclocking, brand new to the market at that time, and of no help whatsoever with any CPU that isn't an Intel Arrow Lake.

                • kvemkona day ago
                  Though clarified at the start about Desktop, but missed JEDEC applying, of course, generally for the whole post.
            • 0cf8612b2e1ea day ago
              And? What real world impact will that have for people typing up an email and browsing the web?
              • glitchca day ago
                It majes a huge difference for local AI models.
        • Pet_Anta day ago
          But they are still gonna fab the Zen 6 chips. So for people already with AM5 motherboards populated with RAM but rocking a Zen 4 CPU this could be a good time to upgrade that CPU with your existing setup. You passing this generation just means less competition for those CPUs which should make them even cheaper.
          • Machaa day ago
            My understanding is they’re using the same process time for cpus and gpus so they may just be able to reallocate it for datacenter gpus. Sure they’re behind but some of the AI companies have already made deals with them as they just want compute, any compute. So I think the effect might be less than some hope for
        • PunchyHamstera day ago
          and do what, buy now-hideously expensive DDR6?
      • parineuma day ago
        > less demand from new system builders mean depressed prices

        Only if they overestimate demand and overproduce CPUs. Otherwise it will lead to higher prices because there's less economy of scale.

    • burnt_toasta day ago
      Hopefully it settles down soon. DDR4 prices are climbing now as well since more people are sticking with it.

      I'd love to build a new desktop soon but I couldn't justify the cost and am instead building out a used desktop that's still on ddr4 / lga1151.

      • nottorpa day ago
        Holy ram prices man!

        I just checked how much the 64 Gb ddr4 in my desktop would cost now... it starts at 2.5 times what i paid in 2022.

        Sorry AMD, I would maybe like a new desktop but not now.

    • XCSmea day ago
      I hope they'll release a new AM4 CPU

      Something like 5900x on 2nm or 4nm

  • bikelanga day ago
    I’m sure there are a plethora of technical reasons it’s impractical - but my dream is a big, unified L3 cache across their CCD chiplets. Maybe 256mb in size for the x950 x3d chips.
    • hedgehoga day ago
      There are challenges with really big monolithic caches. IBM does something sort of like your idea in their Power and Telum chips, with different approaches. Power has a non-uniform cache within each die, Telum has a way to stitch together cache even across sockets (!).

      https://chipsandcheese.com/p/telum-ii-at-hot-chips-2024-main...

      https://www.eecg.utoronto.ca/~moshovos/ACA07/projectsuggesti...

      (if you do ML things you might recognize Doug Burger's name on the authors line of the second one)

    • wmfa day ago
      They could bond multiple CCDs on top of a single large unified L3 die (similar to MI300C) if they wanted to. I've seen no rumors about that though.
    • guywithahata day ago
      I'm currently cache limited by my work and I share your dream
  • TwoNineAa day ago
    I hope for a little more PCIe lanes so I can run 2 gaming VMs on these and upgrade my old Threadripper.
    • dogma1138a day ago
      There is fuck all difference between x8 and x16 for gaming. Heck with PCIe5 even dropping to x4 is borderline noticeable outside of benchmarks.
      • Sohcahtoa82a day ago
        100% this

        The PCI-Express bus is actually rather slow. Only ~63 GB/s, even with PCIe 5 x16!

        PCIe is simply not a bottleneck for gaming. All the textures and models are loaded into the GPU once, when the game loads, then re-used from VRAM for every frame. Otherwise, a scene with a lowly 2 GB of assets would cap out at only ~30 fps.

        Which is funny to think about historically. I remember when AGP first came out, and it was advertised as making it so GPUs wouldn't need tons of memory, only enough for the frame buffers, and that they would stream texture data across AGP. Well, the demands for bandwidth couldn't keep up. And now, even if the port itself was fast enough, the system RAM wouldn't be. DDR5-6400 running in dual-channel mode is only ~102 GB/s. On the flip side the RTX 5050, a current-gen budget card, has over 3x that at 320 GB/s, and on the top end, the RTX 5090 is 1.8 TB/s.

        • nineteen99915 hours ago
          > All the textures and models are loaded into the GPU once, when the game loads, then re-used from VRAM for every frame. Otherwise, a scene with a lowly 2 GB of assets would cap out at only ~30 fps.

          Ah, not really these days, textures are loaded in/out on demand, at multiple different mipmap levels, same with model geometry and LOD's. There is texture and mesh data frequently being cached in and out during gameplay.

          Not arguing with your points around bus speeds, and I suspect you knew the above and were simplyifing anyway.

        • 16 hours ago
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        • rowanG07716 hours ago
          You are correct that games generally are not PCIe limited. But you are incorrect that games just upload everything ones and be done. Most modern engines are most certainly streaming in and out assets all the time.
      • magicalhippoa day ago
        Main problem seems to be they're kinda badly utilized (IMHO) on many motherboards. Most seem to go with two x16 slots so you get x8 lanes in both.

        There are some exceptions, but I haven't seen one with for example four x16 slots that support PCIe 5.0 x4 lanes with bifurcation.

        • dogma1138a day ago
          You can buy add-in cards that do lane bifurcation

          E.g. https://www.ebay.co.uk/itm/126656188922

          Most motherboards don’t go beyond 2x8 with 2x16 physical slots because there is little actual use for it and it costs quite a bit of money.

      • johnbellonea day ago
        The biggest difference for me for PCIe 5.0 has been additional bandwidth for my M2 drive.
        • kijina day ago
          Faster M.2 drives are great, but you know what would be even greater? More M.2 drives.

          I wish it was possible to put several M.2 drives in a system and RAID them all up, like you can with SATA drives on any above-average motherboard. Even a single lane of PCIe 5.0 would be more than enough for each of those drives, because each drive won't need to work as hard. Less overheating, more redundancy, and cheaper than getting a small number of super fast high capacity drives. Alas, most mobos only seem to hand out lanes in multiples of 4.

          Maybe one day we'll have so many PCIe lanes that we can hand them out like candy to a dozen storage devices and have some left to power a decent GPU. Still, it feels wasteful.

          • toast0a day ago
            > Alas, most mobos only seem to hand out lanes in multiples of 4.

            AFAIK, the cpu lanes can't be broken up beyond x4; it's a limitation of the pci-e root complex. The Promontory 21 chipset that is mainstream for AM5 does two more x4 and four choose sata or pci-e x1. I don't think you can bifurcate those x4s, but you might be able to aggregate two or four of the x1s. And you can daisy chain a second Prom21 chipset to net one more x4 and another 4 x1.

            Of course, it's pretty typical for a motherboard to use some of those lanes for onboard network and what nots. Nobody sells a bare minimum board with an x16 slot, two cpu based x4 slots, two chipset x4 slots, and four chipset x1 slots and no onboard perhipherals, only the USB from the cpu and chipset. Or if they do, it's not sold in US stores anyway.

            If pci-e switches weren't so expensive, you might see boards with more slots behind a switch (which the chipsets kind of are, but...)

          • wpma day ago
            The M.2 form factor isn't that conducive to having lots of them, since they're on the board and need large connectors and physical standoffs. They're also a pain in the ass to install because they lie flat, close to the board, so you're likely to have to remove a bunch of shit to get to them. This is why I've never cared about and mostly hated every "tool-less" M.2 latching mechanism cooked up by the motherboard manufacturers: I already have a screwdriver because I needed to remove my GPU and my ethernet card and the stupid motherboard "armor" to even get at the damn slots.

            SATA was a cabling nightmare, sure, but cables let you relocate bulk somewhere else in the case, so you can bunch all the connectors up on the board.

            Frankly, given that most advertised M.2 speeds are not sustained or even hit most of the time, I could deal with some slower speeds due to cable length if it meant I could mount my SSDs anywhere but underneath my triple slot GPU.

            • kvemkona day ago
              > I could deal with some slower speeds due to cable length

              Observing server mainboards reveals many PCIe 5.0 connectors for cables to attach PCIe-SSDs looking similar to SATA ones.

            • jononora day ago
              Agree that M.2 is fiddly. PCIE cards with M.2 sockets are nice nice for desktops and servers, then one can just unplug it to do operations.
          • Aurornisa day ago
            There are add-in cards with PCIe switch chips that will let you put a large number of drives into a single PCIe slot.
        • ihswa day ago
          [dead]
      • Gracanaa day ago
        Your comment is basically the "tl;dr" of this Techpowerup article (which is great and people should read it if they are unconvinced or curious): https://www.techpowerup.com/review/nvidia-geforce-rtx-5090-p...
    • toast0a day ago
      You're not getting more lanes without a new socket. Or a PCIe switch, which is expensive.
    • Szpadela day ago
      for that you need new socket and motherboard. you need to physically route those extra lanes to pcie slots or other components
      • wtallisa day ago
        And even when AMD does move their mainstream desktop processors to a new socket, there's very little reason to expect them to be trying to accommodate multi-GPU setups. SLI and Crossfire are dead, multi-GPU gaming isn't coming back for the foreseeable future, so multi-GPU is more or less a purely workstation/server feature at this point. They're not going to increase the cost of their mainstream platform for the sole purpose of cannibalizing Threadripper sales.
    • dmos62a day ago
      Had to look up what vm gaming is. What's your motivation? If you don't mind sharing.
    • rowanG07717 hours ago
      This. I needed a high speed link between two PCs and bought a mellanox card, cue me surprised that a consumers PCs do not have enough PCIe lanes to handle both a thickboii GPU and a thickboii 200GBe mellanox card...
  • charleshna day ago
    They should be reintroducing the 3D vcache [0] variants (X) in EPYC, with a higher cache/core ratio, that was present in EPYC4 (e.g. 9684X [1]) they for some reason wasn't available in EPYC5.

    Makes a massive difference at high density and utilisation, with the standard cache/core performance can really degrade under load.

    [0] https://www.amd.com/en/products/processors/technologies/3d-v...

    [1] https://www.amd.com/en/products/processors/server/epyc/4th-g...

  • pmontraa day ago
    "7 GHz clock speed"

    When did the GHz race start again?

    • phirea day ago
      It never stopped.

      Just takes backwards steps from time to time with major architectural innovations that deliver better performance at significantly lower clock speeds. Intel's last backwards step was from Pentium 4 to Core all the way back in ~2005. AMD's last backwards step was from Bulldozer (and friends) to Zen in 2017.

      7GHz is ridiculous and probably just a false rumour, but IMO; Intel and AMD are probably due for another backwards step, they are exceeding the peek speeds from the P4/Bulldozer eras. And Apple has proved that you can get better performance at lower clock speeds.

      • Hikikomori3 hours ago
        Intels plan for P4 was to scale to 10Ghz. Its always been a race but plans don't always work out.
    • muroa day ago
      Rumors = the author just made something up
      • ziml77a day ago
        Similarly:

        Leaks = the author just made something up, but now it ranks extra highly when someone searches for "[upcoming thing] leaks"

        • Sohcahtoa82a day ago
          I hate the term "leak". It used to have meaning.

          Now, it's either a fancy term for "announcement", or people use it synonymously with "rumor".

    • bikelanga day ago
      I remain quite skeptical of that. Maybe on a purpose built overclocking rig :^)
    • kvemkona day ago
      Yeah, first of all we need to get 6 GHz with Zen 6.
  • kvemkona day ago
    > This increases the maximum core count per chiplet from 8 to 12. Furthermore, it increases the L3 cache per CCX/CCD from 32 MB to 48 MB.

    I'd say the amount of L3 is not increased but adapted/scaled to the increased core count, since per each core there is still the same amount of cache available as before.

    We get faster cores, so we need to get from 5600 to e.g. 6000 DDR5. Since core count is increased by 50%, we'd need 9000... DDR5^W, well yes, we'd need actually as planed before AM6 and DDR6!

    • wtallis21 hours ago
      There are already DDR5 CUDIMMs at and above 8000 MT/s, and 9600 MT/s has been demonstrated but none are currently in stock. By the time AMD ships Zen 6 desktop processors, the market should be ready with memory modules that will mean even the highest core count Zen 6 parts will be at worst only slightly more bandwidth-starved than their predecessors. And the lower core count Zen 6 CPUs with a single CCD should be able to provide substantially more bandwidth than their predecessors. All without requiring DDR6 yet.
  • Havoc21 hours ago
    Well with the way ram is going my next buy may well land on zen 6/ddr6/pcie6
  • snvzz12 hours ago
    By the time Zen6 launches, there will already be RVA23 chips in the market.

    x86 releases will never again be as interesting.