Discussion RDNA4 + CDNA3 Architectures Thread

[DisEnchantment]

With the GFX940 patches in full swing since first week of March, it is looking like MI300 is not far in the distant future!
Usually AMD takes around 3Qs to get the support in LLVM and amdgpu. Lately, since RDNA2 the window they push to add support for new devices is much reduced to prevent leaks.
But looking at the flurry of code in LLVM, it is a lot of commits. Maybe because US Govt is starting to prepare the SW environment for El Capitan (Maybe to avoid slow bring up situation like Frontier for example)

See here for the GFX940 specific commits

History for llvm/lib/Target/AMDGPU - llvm/llvm-project

The LLVM Project is a collection of modular and reusable compiler and toolchain technologies. - History for llvm/lib/Target/AMDGPU - llvm/llvm-project

github.com

Or Phoronix

More AMD "GFX940" Enablement Work Landing In LLVM - Phoronix

www.phoronix.com

There is a lot more if you know whom to follow in LLVM review chains (before getting merged to github), but I am not going to link AMD employees.

I am starting to think MI300 will launch around the same time like Hopper probably only a couple of months later!
Although I believe Hopper had problems not having a host CPU capable of doing PCIe 5 in the very near future therefore it might have gotten pushed back a bit until SPR and Genoa arrives later in 2022.
If PVC slips again I believe MI300 could launch before it

This is nuts, MI100/200/300 cadence is impressive.



Previous thread on CDNA2 and RDNA3 here

Question - Speculation: RDNA3 + CDNA2 Architectures Thread

Man I have been dying to make this one for a while now. First rumours for RDNA3 are here so new thread time! Just going to start off with this one for now: kopite7kimi on Twitter: "@VideoCardz Ah, I mean a simple mcm design with 10240 cores is not enough. Because the lift from RDNA2 to RDNA3...

forums.anandtech.com

 

[igor_kavinski]

Guy mentioned money is really tight and it could be up to 2 years before he does the platform upgrade. If you want to call that temporary.

At least he's happy to have something new and shiny

I guess it's a matter of perspective. I'm the guy who bought the MGS2 DVD WITHOUT having a proper GPU and not even a DVD drive. Was maybe 6 to 9 months (maybe longer) before I could actually play the game. But it felt good holding the DVD case in my hands and looking at it from time to time. Having no money sucks bad.

 

[DAPUNISHER]

At least he's happy to have something new and shiny

I guess it's a matter of perspective. I'm the guy who bought the MGS2 DVD WITHOUT having a proper GPU and not even a DVD drive. Was maybe 6 to 9 months (maybe longer) before I could actually play the game. But it felt good holding the DVD case in my hands and looking at it from time to time. Having no money sucks bad.

I kept reading the thread, and one of the crew is coming through for him -

Congrats on the 9060 XT upgrade OP!

Just throwing this out there, if you're located in the CONUS I've got spare RAM, NVMe's, SATA SSD's, LGA1200, LGA1700, and AM4 CPU's. I would be willing to ship you a CPU / RAM / Storage combo if you don't mind covering just the shipping cost.

Those of us who can do so do our best to look out for our own here, I figure it would be the least I could do to help and let your 9060 XT really stretch its legs.

 

[igor_kavinski]

Super bless that kind soul!

 

[Thunder 57]

Guy mentioned money is really tight and it could be up to 2 years before he does the platform upgrade. If you want to call that temporary.

I can appreciate that. I have run systems with bottlenecks before. Geforce 3 Ti 200 comes to mind.

 

[igor_kavinski]

Geforce 3 Ti 200 comes to mind.

I had good times with that. It was a used ASUS model with a golden colored heatsink. Looked premium and overclocked well too.

 

[Thunder 57]

I had good times with that. It was a used ASUS model with a golden colored heatsink. Looked premium and overclocked well too.

One of my favorites. Core overclocked nicely but memory not so much. Still great for the time. I kept it until the 9800 Pro.

 

[Timorous]

At least he's happy to have something new and shiny

I guess it's a matter of perspective. I'm the guy who bought the MGS2 DVD WITHOUT having a proper GPU and not even a DVD drive. Was maybe 6 to 9 months (maybe longer) before I could actually play the game. But it felt good holding the DVD case in my hands and looking at it from time to time. Having no money sucks bad.

I had to wait a month before I could use my 5800X3D because I was waiting for MSI to release a bios update for my motherboard.

 

[Heartbreaker]

I get what you are saying, but the consoles are clear on how much vram to include: 12GB. The PS5 is not going away. The series s continues to be the boat anchor for the current gen, but that’s sort of laughable when it gets the Xbox One graphics presets anyway.

12GB was the sweet spot for a minimum of this GPU generation with aspirations of solid performance and avoiding stuttering with out of the box settings for games.

Yet here we are.

Hopefully 3GB GDDR7 modules really do clean this up in 2026 onwards.

IMO this console generation are targeting 10GB. XB Series X, has 10GB of fast memory and 6 GB of slow memory. It's fairly obvious that the 10GB fast memory is the GPU memory for XBSX.

 

[blckgrffn]

IMO this console generation are targeting 10GB. XB Series X, has 10GB of fast memory and 6 GB of slow memory. It's fairly obvious that the 10GB fast memory is the GPU memory for XBSX.

True, but the PS5 exclusives seem to continually make the naughty list of games that need more memory.

MS just isn't driving requirements like Sony is, IMO.

Either way, more than 8GB - either 10 or 12 - is the way to go.

I stand by that both nvidia and AMD should have just skipped the 8GB Ti/XT cards because they are going to age terribly and its annoying to always have to check the memory amount for a SKU with the same name when they offer dramatically different performance and longevity in a growing number (not all) titles.

 

[marees]

Either way, more than 8GB - either 10 or 12 - is the way to go

1080p max — 12gb
1440p max — 16gb
4k max — 24gb

If you don't follow the above then already in Id.tech based Indiana jones you'll have to reduce texture cache pool

& yes all PS5 games can't play 1080p quality upscaled on 8gb

Then all open world games with nanite like tech are again hit by 8gb cards including the extremely well optimized Kingdom Come Deliverance 2 based on cry engine

& then 'unoptimized' old games such as Forza Horizon 5 will make you cry if you play it on 8gb cards

 

[CakeMonster]

I have this uneasy feeling about the next gen consoles and VRAM. I really hope we won't get stuck being even more starved at the end of the next generation because the consoles continue the current PC trend of equipping way too little.

 

[jpiniero]

I have this uneasy feeling about the next gen consoles and VRAM. I really hope we won't get stuck being even more starved at the end of the next generation because the consoles continue the current PC trend of equipping way too little.

The PS6 is most likely going to have 24. 4 GB chips should be available at some point, which would mean the 128-bit cards have 16.

 

[CakeMonster]

Yeah 16 or 24 is what worries me, I can't imagine that in 10 years it will plague and bother us any less than 16GB is now. And if current consoles had proper capabilities to run RT, ML upscaling, and various AI models, 16GB would be even more problematic today. In the time frame of next gen I suspect bigger AI models for various purposes will be even more important, and if not, anything less than 32GB still seems risky given the historical typical 2x or more increase.

 

[blckgrffn]

I have this uneasy feeling about the next gen consoles and VRAM. I really hope we won't get stuck being even more starved at the end of the next generation because the consoles continue the current PC trend of equipping way too little.

I feel like its a safe bet that they include at least 50%-100% more ram, that seems to be the trend and if feels like the PS5 Pro was not granted more ram on purpose. All things considered, memory can be a cheap commodity when purchased in massive volumes for years like these big consumers probably do. PS5 has 16GB of ram now, for reference. So does the Series X. If you are asking usable GPU RAM, I am guessing 20GB as a minimum.

Now, to age my own self terribly, it seems like we'll hit diminish returns someday? I think we've been saying this for 30 years though, so I am probably just being foolish.

Speaking of aging poorly, I think Nintendo missed the boat on ram on the Switch 2. They should have just matched the 16GB. I know they have somewhat the equivalent of a 10GB fast pool but man, they launched what feels like a year late and still didn't bump this easy spec. It would have been just too easy to have a similar ram footprint as the current gen consoles (total) and baseline gaming PCs/SteamDeck. Just my $.02 but I am still a little in awe over how old the guts of its are at this point anyway.

 

[Saylick]

The PS6 is most likely going to have 24. 4 GB chips should be available at some point, which would mean the 128-bit cards have 16.

Yeah, I suspect that we'd get 24 GB consoles next, but utilizing a 256-bit bus and 3 GB memory chips. Reserve 20 GB for games and I think we'd be in a good place for 4K gaming.

 

[CakeMonster]

Those are both useful perspectives, I absolutely think 24GB is more than 'fine' now, I just worry about the mid and tail end of the next generation which would be 2034-2035 I guess. Maybe indeed we are in the age of diminishing returns, but there's also a lot happening on the software side recently...

 

[Panino Manino]

In theory Radeon is improving. RDNA is a good architecture, however is AMD really closing in the gap?

Once again there's discussion and angry comments that Nvidia is selling less for a higher price:



But seeing these number I realise, each generation renamers a lower tier die as a higher tier card and yet it's enough to compete with AMD.
If Jensen wanted he could really have "killed" Radeon, but the way it is AMD's GPUs are no more than another tool Jensen uses to boost the value of his products and brand.


It's depressing.

 

[Saylick]

Those are both useful perspectives, I absolutely think 24GB is more than 'fine' now, I just worry about the mid and tail end of the next generation which would be 2034-2035 I guess. Maybe indeed we are in the age of diminishing returns, but there's also a lot happening on the software side recently...

If AI upscaling of lower resolution textures takes off, it ought to reduce memory footprint demands I think.

 

[Timorous]

If AI upscaling of lower resolution textures takes off, it ought to reduce memory footprint demands I think.

Or Devs just spend less time optimising textures so they use roughly the same space as now at a lower resolution hoping AI can make up the difference.

 

[Saylick]

Or Devs just spend less time optimising textures so they use roughly the same space as now at a lower resolution hoping AI can make up the difference.

For PC games, I can believe that. I hope for consoles, developers choose to make the most of what hardware they have.

 

[GodisanAtheist]

For PC games, I can believe that. I hope for consoles, developers choose to make the most of what hardware they have.

-Opposite I think. Consoles have some strict limits in place, so they will use AI compression techniques to get to 95% fidelity for a fraction of the space.

PC gamers will get the fully uncompressed high res textures as a no compromises "perk" thanks to the vast unique hardware sets out there and our downloads will be 300gb in size.

 

[Saylick]

-Opposite I think. Consoles have some strict limits in place, so they will use AI compression techniques to get to 95% fidelity for a fraction of the space.

PC gamers will get the fully uncompressed high res textures as a no compromises "perk" thanks to the vast unique hardware sets out there and our downloads will be 300gb in size.

I don't think we're in disagreement here. My statement was in belief that console developers will try to optimize their textures to fit within VRAM, hopefully by using AI upscaling judiciously, while on PC they won't give a crap and will just let textures bloat.

 

[Kepler_L2]

If AI upscaling of lower resolution textures takes off, it ought to reduce memory footprint demands I think.

If you're referring to neural texture compression that's not really "upscaling", it's just a more efficient encoding format using low-precision math.

 

[Timorous]

I'm still not 100% clear on how this is calculated from this explanation.

So all test results get scaled to a baseline of card on test = 100% and all others are scaled off of that. Then for all the tests those different numbers are averaged which then gives you the average relative performance. By scaling it all to a baseline of 100 as Wiz said it avoids certain games having more weight just because they are higher FPS and whatnot.

Game	Test Card FPS	Comparison card	Test Card Baseline	Comparison relative performance
Game A	200	160	100%	80%
Game B	30	20	100%	66%
Game C	1000	1500	100%	150%
Average	410	560	100%	98.7%

As you can see from this example the simple average FPS shows a big advantage for the comparison card because Game C is being weighed a lot more than the other results due to being such a high number. When you change it so that the baseline is 100 and scale the comparison card off of that and average those per game relative performance numbers you get a very different result because suddenly Game C is not most of the weight. If you were to take Game B and double the Test Card FPS to 60fps it would barely move the average FPS results but it would move the relative performance result.

I think you could probably make an argument that the weighting should be inverted. Differences at lower FPS matter more than at high FPS. For example the difference between 20 fps and 30 is a lot more noticeable than 1,500 and 1,000.

 

[eek2121]

I get what you are saying, but the consoles are clear on how much vram to include: 12GB. The PS5 is not going away. The series s continues to be the boat anchor for the current gen, but that’s sort of laughable when it gets the Xbox One graphics presets anyway.

12GB was the sweet spot for a minimum of this GPU generation with aspirations of solid performance and avoiding stuttering with out of the box settings for games.

Yet here we are.

Hopefully 3GB GDDR7 modules really do clean this up in 2026 onwards.

Unless future consoles change, the RAM pool will be shared. Consoles previously had a dedicated pool of VRAM that is shared by the CPU and GPU, with some reserved for the OS, so on paper a console may 16gb, however in practice you may have half that.

Note that I have not looked at the PS5 Pro/switch 2, and don’t follow consoles closely in general.