AMD’s next-generation Zen 4 processor architecture and Socket AM5 motherboards were the hot topic of the Computex trade show this week and PC enthusiasts and PC gamers were hanging off every word of the company’s keynotes. The company has some fascinating new technologies and products in store for fall this year, but AMD’s Robert Hallock, director of technical marketing, spoke to me today, answering some of the most pressing questions enthusiasts have about it’s new CPUs and new platform
You can read it all here or watch the interview below.
In short, we learn why Socket AM5 will be DDR5 only, how it’s new 3D V-Cache technology will appear in future Ryzen 7000 CPUs, why it has the X670E chipset as well as X670 and if Threadripper is dead or AMD has the door open for it to return.
Antony: I’d like to start with the present, then talk about Zen 4 stuff and the questions are both my own and also from my readers. So with the present then, The Ryzen 7 5800X3D was a very interesting addition to Socket AM4 and maybe even unexpected too given Zen 4’s proximity. Can you tell us why AMD decided to release it now – was it to showcase 3D V-cache or to bolster gaming performance against some decent competition?
Robert: Can I answer yes to all of those? I think what you’ve seen from AMD and I’m not sure how often its recognized is we’ve been pushing packaging technology very hard. We get very focused on this Zen or that Zen or what process node we’re on. But there’s this third column of progress that AMD’s been making when we went from monolithic dies to chiplets and mixed nodes and now with stacking and that’s a five/ six year road map in the same way that Zen has been.
So the time felt right to show what we can do with 3D stacking. Yes for gaming performance but also to give people a technical preview of where we’re headed outside of Zen and what we can do for performance without iterating process or architecture. So you see AMD now with htree different columns of performance control that are all very significant and kind of equal in terms of benefit and all of them will play a role in our road map going forward. So it’s one part look what we can do and one part we want to give a really strong finish to Socket AM4, even though its not going anywhere. We wanted to end on a high note.
Antony: As far as 3D V-cache goes, is this going to be included on all Ryzen 7000 CPUs or will there be standard models and X3D models like we have with the Ryzen 7 5800X and Ryzen 7 5800X3D.
Robert: I can’t go into details yet, but I do want people to know that 3D V-Cache will live on, there will be Zen 4 with 3D V-Cache and it’s not a one-off technology.
Antony: Is the 5800X3D the last processor we’ll see launched on Socket AM4?
Robert: I would say probably not. I don’t really know what we plan to do with Socket AM4 but I think you saw Lisa talk about AM4 will continue, it will live on and it certainly has huge demand both from DIY builders and system customers. Could there be more AM4? Probably? But I don;t have anything specific to say on that.
Antony: Are socket AM4 and Ryzen 5000 going to sit alongside Socket AM5 in the same way we’ve seen Ryzen 3000 sit alongside Ryzen 5000?
Robert: Yeah you’ll absolutely see AM4 live on in parallel carrying lower price points and more mainstream options. That’s not to say Zen 3 is slow by any means. There’s definitely an opportunity for it going forwards.
Antony: Socket AM4 has had a gloriously long lifespan made even sweeter by the new backwards compatibility of Ryzen 5000 CPUs with first generation AM4 boards recently – Is AMD aiming for a similarly-long lifespan with socket AM5? Or will it be limited to two or three generations of CPUs?
Robert: I don’t know yet – that’s the honest answer. We’re still early in the build up of AM5. It releases in the fall but it’s a long way away. One of the things we want to clear up is what this looks like. Our users expect transparency on this topic. But we just don’t have an answer yet.
Antony: So a popular question I’ve seen is whether DDR5 memory will be the only memory type supported across all chipsets – that certainly seems the case. Was support for DDR4 as well as DDR5 considered at all and what can you say to enthusiasts that are concerned about current high prices of DDR5 compared to DDR4 and the limited gains the former offers?
Robert: It all comes together as a macro topic of supply and pricing and what I want to say is we’ve been in active conversations with all the memory-related vendors for months now and we wanted to make sure their supply output matches our supply forecast. We’re not seeing any challenges in the supply chain ad in fact are very excited about Socket AM5 being exclusively DDR5. I want to be very clear about that – there will be no DDR4 support on Socket AM5.
This will create that demand and economies of scale that doesn’t exist today. It’s the chicken and egg. You need adopters to bring the price down but if you give them an alternative they’re not going to adopt it. So I think it’s fair to say that memory vendors were somewhat frustrated by that (Intel supporting both with its 12th Gen CPUs).
So we’re all in on DDR5, it’s a great technology, lower power, the overclocking is better, the density is better and that’s why we’re exclusively relying on it. People will see those economies of scale and exclusivity bring the prices down and improve the overall diversity in the market.
Antony: Memory speed has been very intertwined with CPU performance in the past due to underpinnings of the Zen architecture and Infinity Fabric. Can you tell us more about how Zen 4 scales with DDR5 and its timings? Is opting for some of the faster DDR5 kits going to yield significantly more performance in the same way going for say a 3600MHz kit did with Zen 3 compared to a 2666MHz kit.
Robert: I would say that in terms of overclocking, Zen 4 is like Zen 3 or Zen 2. The features are the same, they function the same, the benefits are similar. There’s not like this massive relearning that has to happen with Zen 4. It’s pretty predictable. “I will say I’m excited by what DDR5 can offer both from a memory clock and fabric clock can do, but it’s too early to go into details.
Antony: Will memory speed have any impact on the performance of the new integrated RDNA2 graphics and what kind of performance can we expect from this?
Robert: That’s a good question. So for us I guess I’d want to highlight that APUs as people think of them today with large graphics cores – that will continue in our roadmap. The Ryzen 7000 series doesn’t signal a change there. The Ryzen 7000 series only has a couple of compute units in the new I/O die simply to enable display outputs plus the video encode and decode right out of the CPU. That will mostly help us in the commercial market where they don’t buy discrete graphics at all.
Now we have full stack of Ryzen CPUs that all have graphics and can drive a display. That’s a good opportunity for us. We know that for enthusiasts they will always have discrete graphics, so we didn’t want to push the integrated graphics too hard in terms of performance. They’re light duty, office-like graphics.
Antony: Moving on to Zen 4 then and something that’s generated a huge amount of interest is how the Zen 4 CPUs will balance frequency with IPC and power consumption – it looks very different to Zen 3 here. Firstly, we’ve seen some impressive frequencies demoed this week and we know there are some big single-thread performance boosts coming. what if anything can you tell us about IPC improvements?
Robert: Not yet. There are a couple of things I want to say about that 15 percent improvement number. Notice we said greater than 15 percent. The asterix on that is that we’re being conservative on that in four different ways. We’re very excited about the single-thread output, both from process and from IPC points of view and we do fully intend to give people the exact breakdown over the summer. We know it’s a hot topic and we know people expect us to have that transparency. No change there.
On a frequency point of view, all I will say is that the 16 core prototype we demonstrated. All the cores were running at 5.5GHz. There aren’t enough threads in a game to get all cores running at 5.5GHz, but of those that were running, all of them were at 5.5GHz so we’re getting a lot of new headroom out of the new process with Zen 4 so it should provide some real dividends.
Antony: The socket power has increased which I guess is going to allow CPUs to hit higher all-core boost frequencies among other things. We already know that cooler compatibility will remain the same which is great, but will we see increases in cooling requirements as a result? For example will an eight core Zen 4 CPU generate more heat than say a Ryzen 7 5800X?
Robert: That’s a good question. So I think it will manifest in a couple of ways. First I want to say that I actually want to fact check myself from yesterday. I got my wires crossed. 170W TDP is a new option but that’s a socket power of 230W because TDP times 1.35 is always out socket power, so that’s true of 65W, 105W and 170W TDP. So I’ve cleared the air around that.
In terms of coolers, anyone that has a large Noctua cooler or 240mm AIO liquid coolers will be just fine on socket AM5. I myself use Noctua’s NH-D5, but I also want to say that this new 170W option does not signal a broad-based change in how we’re approaching TDPs. So there will still be 65W and 105W. We just wanted an option to expose more multi-threaded performance on higher core count CPUs and frankly we’ve left a lot of that power on the table in the past with lower socket power limits.
So being able to expose that gives us with Zen 4 with frequency, another 50 percent bump in overall compute performance. It’s pretty big. It’s worth it although it won’t be up and down the stack. I think people should understand that every time you shrink a die and add more transistors that does increase the thermal density. It concentrates the heat more, , but that doesn’t mean the process runs hotter or the CPU runs hotter right. It’s just physics. So we’re saying we want people to be able to use Socket AM4 coolers because we think they’re perfectly capable.
Antony: We’re used to different CPUs landing on shelves at launch and having to wait for the entire stack to be available. Is there any information about whether AMD intends to release some or all of the key CPUs at launch this fall?
Robert: Unfortunately this is one of the last things we decide so we don’t have any information on this right now.
Antony: The trio of new chipsets is an interesting choice. What was the main reason for splitting the top end with X670 and X670E? Was this pure down to PCIe 5 support or do you envisage the CPUs with the highest core counts mainly being used by high-end gamers and professionals that might otherwise opt for Threadripper.
Robert: That’s a good question. The decision to split X670 into two chipsets actually goes back to early in the life of X570 where all those boards had PCIe 4 on every motherboard. At the time we listened to the feedback such as people saying we don’t have PCIe 4 graphics or storage devices and I don’t intend to upgrade these for a while, or can you give me an option that doesn’t have PCIe 4 at lower cost.
We felt that with PCIe 5 it was pretty much the same situation and now we have the opportunity to take that feedback seriously and do something different. So the X670E chipset has PCIe 5 on two PEG slots, either one x16 or two x8. Then one NVMe will be PCIe 5 and then PCIe 5 is optional on the standard X670 chipset.
This gives a wider range of X670 chipset motherboards, but not all of them have the added PCIe 5 cost. There will be a wider range of price points and we think people will appreciate that.
Antony: One feature increasing numbers of people are interested in is Thunderbolt 4. Thunderbolt has had limited support so far, but one would probably expect it to be included on flagship motherboards, especially on the X670E chipset. Is there any word on Thunderbolt support yet?
Robert: As we’ve seen at Computex, there are already motherboards with USB 4 support for now and the interoperability there with Thunderbolt is known so the market is already closing that gap.
Antony: I know you probably can’t talk about specific CPU models, but is there any word on cache sizes outside of any 3D V-Cache implementation? Have these remained the same or are they increasing?
Robert: Well we’re doubling the size of L2 cache in Zen 4. It’s always a very fine balance with L2 cache as it takes up a large amount of the core itself, but as Intel has done with Alder Lake as well, as you transition to smaller process nodes it’s a good opportunity to find a new balance between cost and capacity. L2 cache is a nice IPC improvement boosting your hit rate on the L2 cache and not having to reach out further and increase latency. We’ll talk about other caching later.
Antony: In terms of tweaking and overclocking, has anything changed here significantly? I know things that some enthusiasts would like to see are more per-core tweaking and monitoring.
Robert: We’re still working through those overclocking features but for us it’s very early. We have to finish the CPUs and then move on to overclocking side of things closer to the fall.
Antony: AMD has been very aggressive in its push for better boosting technologies. Will you be introducing any new boosting technologies with Zen 4?
Robert: AMD will use the same Precision Boost 2 algorithm that’s used today. The great thing about that is that it scales with whatever process technology or frequency headroom you have. That’s why we built it the way that we did because it’s kind of a one size fits all solution. If we pick up a ton of frequency headroom or multi-thread ability or whatever, Precision Boost 2 can expand to fit and that will be the case with Zen 4.
Antony: Following on from that, manual overclocking has had an increasingly small part to play with Ryzen thanks to more automatic methods such as Precision Boost Overdrive 2, and only really worth it with specific CPUs or specific workloads. Do you think Zen 4 will lean more towards getting more out of the CPU at stock speed or will manual overlocking still have its place in a PC enthusiasts tool box?
Robert: So for us, this is a philosophical choice we make. Let’s be clear about what overclocking is. Yes it’s fun, yes it’s exciting, yes it feels like you got something for free. But for a vast majority of users, the performance that’s in the chip is hidden behind a warranty violation and that for us is not right. We don’t want people to have to break their warranty to get this extra frequency the CPU is capable of and that is why we bin our parts so aggressively to take advantage of everything that’s there and Zen 4 will be no different. Users shouldn’t expect big changes in the way we approach CPU frequency overclocking. Precision Boost Overdrive will still be beneficial, Curve Optimizer will still be beneficial, memory overclocking will still be beneficial.
Antony: Finally, a question that’s dear to my heart and also plenty of my readers is Threadripper. With the inclusion of a high-end chipset in X670E with full PCIe 5 support and even more multi-threaded performance with the new 16-core Zen 4 part, presumably the Ryzen 9 7950X, It’s looking increasingly unlikely we’ll see successors to the Threadripper 3960X, 3970X and 3990X. Is a new high-end Desktop CPU in AMDs plans at all?
Robert: All I can say is Threadripper is not going anywhere.
I’d like to thank Robert for his time in answering these questions about Zen 4 and the new Ryzen 7000 series. You can read more below and don’t forget to follow me here on Forbes using the link at the top. You can also check me out on YouTube, Instagram, Twitter and Facebook.