AMD's CDNA 4 Architecture Announcement

(chipsandcheese.com)

170 points | by rbanffy 108 days ago

5 comments

  • jauntywundrkind 107 days ago
    Faster small matrix, for AI. Yup, that seems like good fit for what folks want.

    Supercharging the Local Data Share (LDS) that's shared by threads is really cool to hear about. 64 -> 160KB size. Writes into LDS go from 32B max to 128B, increasing throughout. Transposes, to help get the data in the right shape for its next use.

    Really really curious to see what the UDNA unified next gen architectures look like, if they really stick to merging Compute and Radeon CDNA and RDNA, as promised. If consumers end up getting multi-die compute solutions that would be neat & also intimidatingly hard (lots of energy spent keeping bits in sync across cores/coherency). After Navi 4X ended up having its flagship cancelled way back now, been wondering. I sort of expect that this won't scale as nicely as Epyc being a bunch of Ryzen dies. https://wccftech.com/amd-enthusiast-radeon-rx-8000-gpus-alle...

  • incomingpain 107 days ago
    I bought a radeon 9060. ROCM works. I'm getting ~40 tokens/sec out of Phi4: 14B

    BEWARE: I was running fully patched ubuntu 24 LTS and I needed to upgrade to ubuntu 24.10 and then ubuntu 25 before the drivers worked. Painful.

  • robjeiter 107 days ago
    When looking at inference is AMD already on par with Nvidia?
    • moondistance 107 days ago
      Yes, for many applications.

      Meta, OpenAI, Crusoe, and xAI recently announced large purchases of MI300 chips for inference.

      MI400, which will be available next year, also looks to be at least on par with Nvidia's roadmap.

      • moondistance 107 days ago
        (this is also why AMD popped 10% at open yesterday - this is a new development and talks from their 2025 "Advancing AI" event were published late last week + over the weekend)
      • christkv 107 days ago
        Is the software stack still lacking?
        • OneDeuxTriSeiGo 107 days ago
          Yeah it's still a few years behind but it's getting better. They are hiring software and tooling engineers like crazy. I keep tabs on some of the job slots companies have in our area and every time I check AMD they always have tons of new slots for software, firmware, and tooling (and this has been the case for ~3 years now).

          They've been playing catch up after "the bad old days" when they had to let a bunch of people go to avoid going under but it looks like they are catching back up to speed. Now it's just a matter of giving all those new engineers a few years to get their software world in order.

          • storus 107 days ago
            They pay hardware rates to software engineers (principal engineer at the salary level of a decent fresh graduate) so I won't be too optimistic about them attracting software people that would propel them forward.
            • OneDeuxTriSeiGo 107 days ago
              At least where I live (very much not west coast), their SW and HW rates are at or above what we normally see in this area.
            • latchkey 107 days ago
              Stock is undervalued. If you get in now and it pops over the next few years, it'll likely make up for lower compensation.
              • MegaButts 107 days ago
                You don't need to work at AMD to buy their stock.
                • latchkey 107 days ago
                  True, but if you don’t have a job, where’s the money for buying stock coming from?
                  • alemanek 107 days ago
                    If you are what AMD needs to catch up then you can just go work for NVidia for 3x the pay. This market sucks but top tier engineers in the niche they need are not a dime a dozen.
                    • latchkey 107 days ago
                      It isn't always about the money.
                      • MegaButts 106 days ago
                        Then why is your original comment about compensation?
                        • latchkey 106 days ago
                          What I said was: “it’ll likely make up for lower compensation.”

                          The point is, someone might join AMD because they believe in the mission, not just for the paycheck. I followed that with: “It isn’t always about the money,” which is consistent with my original comment.

                          The real subtext is something I care deeply about: Nvidia is a monopoly. If AI is truly a transformative technology, we can’t rely on a single company for all the hardware and software. Viable alternatives are essential. I believe in this vision so strongly that I started a company to give developers access to enterprise grade AMD compute, back when no one was taking AMD seriously in AI. (Queue the HN troll saying that nobody still does.)

                          If the stock goes up while they’re there, great, that’s a bonus.

                • iszomer 107 days ago
                  We're forbidden to trading our own stock anyway, SEC regulation on insider trading and all.
                  • vlovich123 107 days ago
                    You’re forbidden from shorting. Buying is completely allowed unless you are classified an insider and even then trades are open for I believe a month after quarterly results.
              • almostgotcaught 107 days ago
                You're "talking your book".
            • varelse 107 days ago
              [dead]
          • zombiwoof 107 days ago
            They pay terrible and still have legacy old guard managers. If you try to innovate on software you should look elsewhere or really make sure your manager knows what’s what
        • martinald 107 days ago
          FWIW for the first time in 2+ years I managed to compile llama.cpp with ROCm out of the box and run a model with no problems* on Linux (actually under WSL2 as well), with no weirdness or errors.

          Every time I have tried this previously it has failed with some cryptic errors.

          So from this very small test it has got way better recently.

          *Did have problems enabling the WMMA extensions though. So not perfect yet.

          • halJordan 107 days ago
            If this has been an issue for two years, then it's not rocm or llama.cpp problem.
            • martinald 107 days ago
              Oh I'm sure you are right its operator error, but I'd always have some issue installing rocm and getting the paths right or something. This is the first time I've managed to install rocm following the commands exactly and then compile llama.cpp without having to adjust anything.

              BTW, this kind of dev experience does really matter. I'm sure it was possible to get working previously; but I didn't have the level of interest to make it work - even if it was somewhat trivial. Being able to compile out of the box makes a big difference. And AFIAK this new version is the first to properly support WSL2, which means I don't have to dual boot to even try and get it working. It's a big improvement.

            • vlovich123 107 days ago
              You can blame the user for not using the tools correctly or the manufacturer for making difficult to use tools that aren’t straightforward or don’t work in various non happy path conditions (ie unreliable installers).

              For example, to this day installing MSVC doesn’t make a default sane compiler available in a terminal - you have to open their shortcut that sets up environment variables and you have to just know this is how MSVC works. Is this a user problem or Microsoft failing to follow same conventions ever other toolchain installer follows?

        • moondistance 107 days ago
          Yes, big time, but there continues to be lots of progress.

          Most importantly, models are maturing, and this means less custom optimization is required.

          • martinald 107 days ago
            Yes I'd agree with that. There is so much demand for inference which is maturing rapidly that even if a lot of the "R&D" is done on NVidia cards because of their (vastly, let's be fair) software stack, if AMD is competitive on the inference side (and perhaps more importantly have shorter lead times) then doing the inference on AMD is still an enormous market.

            I suspect we will (or already are?) at a point where 95%+ of GPUs are used for inference, not training.

    • latchkey 107 days ago
  • bee_rider 107 days ago
    Machine learning is, of course, a massive market and everybody’s focus.

    But, does AMD just own the whole HPC stack at this point? (Or would they, if the software was there?).

    At least the individual nodes. What’s their equivalent to Infiniband?

  • icf80 107 days ago
    no UDNA ? any news ?