News AMD GPU Roadmap: RDNA 3 With 5nm GPU Chiplets Coming This Year

My money's on them using the approach with Zen 3: one centralized I/O chip with as many chiplets as you need.
I thought of this at first but then thought, no way, that would be a mess. Because then there would be an IO chiplet for the high-end, mid-range, and low-end. Or maybe it's only on the high-end and might make more sense?

But I'm betting there will be a design where you get something like a 256-bit interface to GDDR6 from a single chip, with a big Infinity Fabric link to another chip. Or maybe 192-bit with a 128-bit wide interface to be used for interchip communications? I don't know, I suppose it depends on how far they scale. Will this be just a dual-chip solution, or will it scale up to three or four chips? MI250X and the images of MI300 make me think it will be up to 4-way, with each chip having some local memory and a wide link or two to another chip.
 
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I thought of this at first but then thought, no way, that would be a mess. Because then there would be an IO chiplet for the high-end, mid-range, and low-end. Or maybe it's only on the high-end and might make more sense?

But I'm betting there will be a design where you get something like a 256-bit interface to GDDR6 from a single chip, with a big Infinity Fabric link to another chip. Or maybe 192-bit with a 128-bit wide interface to be used for interchip communications? I don't know, I suppose it depends on how far they scale. Will this be just a dual-chip solution, or will it scale up to three or four chips? MI250X and the images of MI300 make me think it will be up to 4-way, with each chip having some local memory and a wide link or two to another chip.
The only thing that keeps me from thinking they'll do something like glue two fully enabled GPUs together with a high speed link to resolve the memory sharing issue is that rendering games is still a real-time application. Every other setup with a multi-chip system I've seen runs tasks that aren't really real-time, just that it's better if it runs the thing faster. Needing to martial and share data tends to add latency, which will eat in to the minimum frame time achievable.

I guess we'll just have to wait and see!
 
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Bikki

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Apple is first one on the scene with M1 ultra, gluing 2 gpus for everyday graphic. That and realtime ray traycing is the holy grail of gpu world. If amd can have x4 gpus in one chip and x2 ray tray, we may very well be living in the future this year.
 

jp7189

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The only thing that keeps me from thinking they'll do something like glue two fully enabled GPUs together with a high speed link to resolve the memory sharing issue is that rendering games is still a real-time application. Every other setup with a multi-chip system I've seen runs tasks that aren't really real-time, just that it's better if it runs the thing faster. Needing to martial and share data tends to add latency, which will eat in to the minimum frame time achievable.

I guess we'll just have to wait and see!
I agree that a hub with a massive infinity cache thats shared by all gpu chiplets seems to make the most sense. I would also think the frontend/scheduler would have to live there as well. The gpu chiplets would then just be much simpler things. There's also a lot of stuff you don't want to duplicate like media decoders, display outputs, etc. I would expect all that to move to the hub.

On the flip side, I agree with what Jared said. It might be hard for that to be cost effective on the low-end to require a hub to be pair with a single gpu chiplet. If they do use identical chiplets without a hub, i think frame time consistency will be tough to manage, and the burden on the driver team would likely be much higher.
 
Apple is first one on the scene with M1 ultra, gluing 2 gpus for everyday graphic. That and realtime ray traycing is the holy grail of gpu world. If amd can have x4 gpus in one chip and x2 ray tray, we may very well be living in the future this year.
If we were to consider the chiplet strategy as using multiple chips to provide additional performance as a single product, then that honor goes to at least ATI with their Rage Fury MAXX. Though if you want to stretch this out further, a company did make Voodoo2 SLI on a single card.

Also since you mentioned it I did want to see how the M1 Ultra performs over the M1 Max. It looks like it has the same performance uplift as any other multi-GPU setup.
 

PiranhaTech

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GPU-wise, this might not do much and might actually lower the performance a bit. However, I could be wrong since AMD in the Ryzen 5000 series got around the bottlenecks that earlier Ryzen chiplet-based CPUs had, so it could be a temporary hit. There's also a chance that it'll increase

Where it might matter more is the SoC game. This might make Radeon integration easier into Ryzen. However, Ryzen isn't the only factor. What does this mean for ARM? There's an interconnect standard coming out, and if AMD can easily integrate Radeon into ARM, that can be a huge factor. There has been Radeon in Samsung ARM chips.

Okay, what if Microsoft wanted to do their own SoC for the next Xbox generation? AMD can still potentially offer Ryzen and Radeon.