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

 

[Bigos]

PS does not run Linux

 

[Shmee]

Odds are the top Navi 48 might be substantially faster than the 7900XTX in games with heavy raytracing.

I don't really care about ray tracing though. I want raw performance in my games, and good FPS overall. I generally turn off RT and tweak settings for high, smooth FPS if possible.

Also the 7900XTX beats the RTX 4090 in some games, or at least it did when I was buying. One of them was COD MWII. I tend to agree that I will probably be waiting sometime for a GPU upgrade.

 

[SolidQ]

One of them was COD MWII.

Still beating with new

Spoiler

 

[Aapje]

Still beating with new

All CoDs are just the same engine, with some tweaks/improvements for each version.

 

[soresu]

All CoDs are just the same engine, with some tweaks/improvements for each version.

We're well past Ship of Theseus levels of rebuild vs the original engine Infinity Ward cobbled together from an id Tech derivative.

Almost certainly completely rebuilt at least once, possibly twice by now.

 

[igor_kavinski]

PS & Valve are both on linux.

Playstation is on a heavily modified BSD distro I think. So more Unix-y.

 

[igor_kavinski]

PS6 likely to be RDNA 6

There will be no RDNA 6. It will be called UDNA 6.

 

[Tuna-Fish]

There will be no RDNA 6. It will be called UDNA 6.

Are you sure about the 6?

I can also sort of see them using a numbering based on CDNA, or starting over from 1.

 

[branch_suggestion]

Well there's your answer on what node it uses, $700 means N4P without a doubt.
The goal was always getting fidelity mode to 60fps.

 

[SolidQ]

$700 means N4P without a doubt.

and 800 euro lol, seems sony testing price before ps6

 

[branch_suggestion]

and 800 euro lol, seems sony testing price before ps6

It will be the new normal, admittedly I expected this pricing for the base consoles but next gen will be $800 for starters, maybe even more.
Pricing here was what I expected with no peer comp.

 

[igor_kavinski]

Are you sure about the 6?

Well, almost.

So, going forward, we’re thinking about not just RDNA 5, RDNA 6, RDNA 7, but UDNA 6 and UDNA 7.

That's a confusing statement but my guess would be that RDNA 6 will be renamed to UDNA 6.

 

[igor_kavinski]

and 800 euro lol, seems sony testing price before ps6

This is only for early adopters. Once they make enough and the stores/warehouses start filling up, it's gonna get discounted to $550 at the very least. People only went beyond that due to COVID shortages.

 

[SolidQ]

it's gonna get discounted to $550 at the very leas

Let's see how it turns out

off specs

60CU?

 

[Josh128]

So RT uplift went from 4x to 3x to 2x "up to" 3x, lol. Interesting its listed as RDNA 3 and not 3+ or whatever.

Honestly, it looks like a decent hardware uplift combined with the AI new upscaling/frame gen tech, but damn, $700 USD? Is the SOC still on 6nm or did they shrink it??

Tech is painting itself into a corner with these ridiculous prices. AMD still looking for $629 for 9950X when you can get 7950X for $400 and 7950X3D for $429. Its almost like they dont want to sell any. I smell trouble ahead.

 

[adroc_thurston]

Tech is painting itself into a corner with these ridiculous prices.

Welcome to the era of dead Moore's Law.

when you can get 7950X for $400 and 7950X3D for $429

While supplies last*

 

[branch_suggestion]

Let's see how it turns out

off specs

60CU?

2SE/4SA/32WGP (2 disabled for yield)
RDNA3.5 specifically added support for up to 8WGP per SA.
Extremely compute heavy, but otherwise is lacking vs N32, heavily vs N48.
GPU clocks are meh honestly, but there isn't enough membw to bother clocking higher so it uses the slim chassis.
Gotta keep it a simple upgrade over the original.

So RT uplift went from 4x to 3x to 2x "up to" 3x, lol. Interesting its listed as RDNA 3 and not 3+ or whatever.

Custom RDNA3, it is a mix of a lot.

Honestly, it looks like a decent hardware uplift combined with the AI new upscaling/frame gen tech, but damn, $700 USD? Is the SOC still on 6nm or did they shrink it??

Has to be a shrink, surely.

Tech is painting itself into a corner with these ridiculous prices. AMD still looking for $629 for 9950X when you can get 7950X for $400 and 7950X3D for $429. Its almost like they dont want to sell any. I smell trouble ahead.

Eh, things will heat up in holiday season, things are in a holding pattern rn.
The big question is when AMD pulls the RDNA4 trigger, because they are being very coy about it, CES is the simple answer but it would be very interesting to launch the day before the $2k+ NV brick with a <$500 value king.
A simple statement of intent to hold things out until UDNA1 in its MCP glory is ready.

 

[marees]

Interesting its listed as RDNA 3 and not 3+ or whatever.

Raster on 3
RT uses features from 4. He specifically mentioned that some RT hardware is increased

 

[SolidQ]

RT uses features from 4. He specifically mentioned that some RT hardware is increased

Seems confirmed by Sony
PS5 Pro uses the new advanced [ray tracing] feature sets that AMD created as the next step in their roadmap architecture," Cerny told me. "But if you look around, there are no other AMD GPUs that use it yet. We motivated the development, and I'm very happy we did so -- the response from the developers has been extraordinarily grea

 

[Josh128]

Also interesting is that some sites are listing it as having an XDNA2 NPU integrated into the SOC, and that is what powers the new AI upscaling. Quite interesting if true.

AMD Debuts New SoC With 60 Compute Units, Faster GDDR6 Memory, Advanced Raytracing & PSSR AI Upscaling In PlayStation 5 Pro

AMD developed a new custom SoC for Sony's PlayStation 5 Pro, featuring 60 Compute units based on the RDNA architecture & other improvements.

wccftech.com

 

[SolidQ]

Sony add AI upscaling on AMD, hope AMD going with RDNA4 also for AI upscaling, otherwise it's gonna be strange, Sony can do it on AMD GPU, AMD can't

AMD Debuts New SoC With 60 Compute Units, Faster GDDR6 Memory, Advanced Raytracing & PSSR AI Upscaling In PlayStation 5 Pro

AMD developed a new custom SoC for Sony's PlayStation 5 Pro, featuring 60 Compute units based on the RDNA architecture & other improvements.

wccftech.com

Another major feature being announced today is PSSR or PlayStation Spectral Super Resolution which is an AI-driven upscaling method. XDNA 2, the same IP that is powering the NPU for AMD's Strix Point APUs will be used to handle the AI processes on the PS5 Pro.

 

[marees]

it's gonna be strange, Sony can do it on AMD GPU, AMD can't

AMD is a poor company unlike rich Sony that can sell consoles in the range of $800-$1000

 

[Mahboi]

Well there's your answer on what node it uses, $700 means N4P without a doubt.
The goal was always getting fidelity mode to 60fps.

People were yapping that Zen 2 wasn't capable, but apparently it'll be capable enough.
I won't be surprised if it's oscillating between 50 and 60, but it's definitely far from 30. Good jerb SAMD.

 

[Mahboi]

2SE/4SA/32WGP (2 disabled for yield)
RDNA3.5 specifically added support for up to 8WGP per SA.
Extremely compute heavy, but otherwise is lacking vs N32, heavily vs N48.
GPU clocks are meh honestly, but there isn't enough membw to bother clocking higher so it uses the slim chassis.
Gotta keep it a simple upgrade over the original.

I thought the PS5 used GDDR6? Is the Pro's RAM clocked too low?

 

[igor_kavinski]

People were yapping that Zen 2 wasn't capable, but apparently it'll be capable enough.

Wish they had souped it up with 64MB MALL cache. Would've made the price worth it.