Discussion RDNA4 + CDNA3 Architectures Thread

Page 77 - Seeking answers? Join the AnandTech community: where nearly half-a-million members share solutions and discuss the latest tech.

DisEnchantment

Golden Member
Mar 3, 2017
1,747
6,598
136
1655034287489.png
1655034259690.png

1655034485504.png

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
Or Phoronix

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 :grimacing:

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

1655034362046.png

Previous thread on CDNA2 and RDNA3 here

 
Last edited:

Timorous

Golden Member
Oct 27, 2008
1,748
3,240
136
Also we don't know how much RDNA3 1TF compared to RDNA4 TF

Technically they are equal but I know you mean we don't know the fps/Tflop ratio. Sure hence why the estimates would have plenty of +/- because it might go up or down.

All things being equal on that front then 3Ghz clocks should get you around OC 7900GRE / 7900XT perf. If IPC is lower then it will be worse and if IPC is more it will be higher.

And yea. PPA is the relevant metric for AMD because that determines margin. Would not be the 1st time AMD have a good PPA advantage over NV but don't do much with it because they don't build a big enough die to drive home the advantage.
 

adroc_thurston

Diamond Member
Jul 2, 2023
3,572
5,155
96
it's can be like RDNA4 50TF = RDNA3 60TF. So that why people compare
useless metric.
If IPC is lower then it will be worse and if IPC is more it will be higher.
it's a SIMD machine it does not have 'IPC'.
All things being equal on that front then 3Ghz clocks should get you around OC 7900GRE / 7900XT perf.
It clocks higher than that.
they don't build a big enough die
Yes, now they have to build a big enough (1.5k+ mm^2 active Si) MCP.
 

SolidQ

Senior member
Jul 13, 2023
540
632
96
useless metric.
i know, but alot people love those comparision.
it's fine if N48 ~ 7900XT + new uarch give advantage in some games + driver not mature yet for RDNA4.
Only big question is left, N48 faster in RT than N31 or not.
Also price is matter, if 600 then meh, if 500 is fine.
 

SolidQ

Senior member
Jul 13, 2023
540
632
96
Why bother if it can't run on consoles at decent speed?
That what people don't understand. NV doesn't have consoles, so they can do whatever they want
Alot people thinking, if PS5 would have NV gpu, that would be much better RT, but they forgot Die Area not rubber.
But still AMD should do already to prepare good quality for PS6, at least like Xess have both versions
 

SolidQ

Senior member
Jul 13, 2023
540
632
96
AMD carpets out some 200WGP tiled monstrocity
and people would think before release, AMD won't compete with Blackwell, even with RDNA5
like was amd can't beat RTX 3070/2080ti

offtopic
That true, what Switch2 DLSS is limited?


Found this
83e0430f68a5cfafeb0c3bfcf0ef16f3.png


My assuming is that because RDNA3/3.5 and 4 have difference WGP. Right?
 
Last edited:

gdansk

Platinum Member
Feb 8, 2011
2,962
4,493
136
Gamers are so influenced by halo part marketing that I'm not sure it'll be a success in any case.

Secondly, now Nvidia does actually have a feature other than driver FUDD that poor victimized gamers throw a hissy fit if it isn't included (DLSS). At least they are sane enough not to cry when a game doesn't include RT.
 

adroc_thurston

Diamond Member
Jul 2, 2023
3,572
5,155
96
Gamers are so influenced by halo part marketing that I'm not sure it'll be a success in any case.

Secondly, now Nvidia does actually have a feature other than driver FUDD that poor victimized gamers throw a hissy fit if it isn't included (DLSS). At least they are sane enough not to cry when a game doesn't include RT.
Yeah but you can't win against hundreds of WGPs.
Simple and brutal!
 

Mahboi

Golden Member
Apr 4, 2024
1,033
1,897
96
I'd bet all my money that it's an FSR base that they added their own specialisations to.
There is literally no reason to redo an entire in-house upscaler. It's a massive workload and FSR works fine, image quality needs tweaks, but the core system runs hard.

What I'm curious about is the degree of porosity between PSSR and FSR. Like will Sony take FSR, improve it with their AI or whatever tweaks they want, then AMD will pinch bits and bobs that could work for a future iteration? Or it's going to be a hard branch with a completely different direction for FSR?
 

CouncilorIrissa

Senior member
Jul 28, 2023
540
2,120
96
Depends on the settings? Based upon Compubase's results you might be able to do something like CP at 1080p30 PSSR on the PS5 Pro?

It's not going to be like Ada of course.



Seems PS4 Pro sold about 25% of the PS4's in the time period it was available. About 14 million or so.
PS4 Pro was a response to 4K TV and had a GPU that was more than twice as powerful than the original.

PS5 Pro is a much smaller jump if you take into account that half of its compute throughput (33 TFLOPS) comes from VOPD that does very little in games.
It's pretty safe to say that it won't sell nearly as well.