Discussion RDNA4 + CDNA3 Architectures Thread

DisEnchantment · Mar 23, 2022

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

Timorous · Apr 18, 2025

Mopetar said:
Navi 44 has 32 CU based on all reliable information so far. That's the same as a 7600XT.

The 7700 XT was based on Navi 32 and was the cut down chip with 54 CU. That's about 70% more cores over a 9060. Meanwhile the 7900 XTX is only 50% more cores and Navi 32 also benefited from fixes to allow it to clock better than the initial RDNA3 cards.

Maybe the 9060 XT will be an absolute monster in clock speeds, but it'll be power hungry for it. Maybe top silicon can get there, and if it does I'll be impressed, but I think it'll be nipping at the heels of the 7700 XT by 10% across the board at best.

Yet despite the massive spec advantage the 7700XT was only 40% faster than the 7600XT.

And that is really the point. Why would the 32CU 3.2Ghz+ 9060XT offer a much smaller uplift over the 32CU 2.7Ghz 7600XT than the 64CU 3.1Ghz 9070XT does over the 60CU 2.5Ghz 7800XT?

The reality is the 9070XT is 45%-50% ahead of the 7800XT. I see no reason why the 9060XT shouldn't be 35%-40% ahead of the 7600XT and that will put it in 7700XT territory.

adroc_thurston · Apr 18, 2025

Mopetar said:
It's going to need much more than that.

why

Mopetar said:
but how many people want a 9060 XT that draws as much power as a 9070 XT?

How would it draw 304W

Timorous · Apr 18, 2025

Mopetar said:
It's going to need much more than that. The silicon may well be capable of it, but how many people want a 9060 XT that draws as much power as a 9070 XT?

Why would it draw the same power?

The 6600XT clocked 300Mhz higher than the 6900XT and pulled 160W Vs 300W. Even the really power inefficient 6700XT which also clocked 300Mhz higher than the 6900XT pulled 221W Vs the 300W of the 6900XT.

At worst it may draw the same amount of power as the 9070 GRE like the 6700XT drew the same as the 6800.

TESKATLIPOKA · Apr 18, 2025

Mopetar said:
It's going to need much more than that. The silicon may well be capable of it, but how many people want a 9060 XT that draws as much power as a 9070 XT?

It won't be anywhere near 9070XT in power.
I think 200W will be the limit, which will be rather close to RX 9070's 220W.

P.S. I expect a small OC potential.

Mopetar · Apr 18, 2025

adroc_thurston said:
why

because

How would it draw 304W

From its power connectors.

adroc_thurston · Apr 18, 2025

Mopetar said:
because

yeah.

Mopetar said:
From its power connectors.

surely 3*8pin Navi48 boards draw 450W.

Mopetar · Apr 18, 2025

TESKATLIPOKA said:
It won't be anywhere near 9070XT in power.
I think 200W will be the limit, which will be rather close to RX 9070's 220W..

I think that's obvious which is also why I don't think it will hit 7700 XT performance levels.

Even 200W is more than this should ever draw. The estimated die size for Navi 44 is around 150 mm^2. Cooling it becomes more of an issue than powering it at a certain point.

Mopetar · Apr 18, 2025

adroc_thurston said:
yeah.

exactly

surely 3*8pin Navi48 boards draw 450W.

not entirely

adroc_thurston · Apr 18, 2025

Mopetar said:
exactly

No.

GodisanAtheist · Apr 18, 2025

Gawd damn I don't even care how this crap performs anymore, just get as much volume into the market possible to stabilize prices on new cards and drop pricing on used cards.

adroc_thurston · Apr 18, 2025

GodisanAtheist said:
just get as much volume into the market possible to stabilize prices on new cards and drop pricing on used cards.

the last time AMD flooded the channel (Hawaii) they had to do a hueg ass inventory writeoff.
It's just new and interesting levels of NOT HAPPENING.

GodisanAtheist · Apr 18, 2025

adroc_thurston said:
the last time AMD flooded the channel (Hawaii) they had to do a hueg ass inventory writeoff.
It's just new and interesting levels of NOT HAPPENING.

- Mo' volume is better than no volume is all I'm saying

adroc_thurston · Apr 18, 2025

GodisanAtheist said:
- Mo' volume is better than no volume is all I'm saying

Yeah they're probably gonna up the MSS targets but don't expect like flood flood.
So stuff in the channel gonna remain above MSRP given the demand mix.

Mopetar · Apr 18, 2025

adroc_thurston said:
No.

x

itsmydamnation · Apr 18, 2025

Mopetar said:
x

I know your trying to be clever, but your original statement was wrong. Even just from a heat density perspective.

reaperrr3 · Apr 18, 2025

Mopetar said:
I think that's obvious which is also why I don't think it will hit 7700 XT performance levels.

- 64 RDNA4 CUs @304W are about as fast as 70 BW SMs @300W
- 5060 Ti 16GB with 36 SM @180W is ~12% faster than a 7700XT in raster

Even assuming the 5070Ti is held back a bit by the 48MB L2 and considering 36 vs. 32 is a slightly bigger advantage than 70 vs. 64, I'd expect the 9060XT-16GB @180W to be at most ~10-12% or so slower than the 5060Ti-16GB, which would put the 9060XT-16GB on roughly equal footing with the 7700XT in raster.

Maybe it'll be slightly slower on average, but not by much.

Mopetar · Apr 18, 2025

itsmydamnation said:
I know your trying to be clever, but your original statement was wrong. Even just from a heat density perspective.

I'm not sure that's the case. When you get to the high end of the silicon the power use starts to scale as a cube function as the voltage increase necessary for frequency increase becomes linear.

Even if the silicon were capable of the clock speeds necessary to give comparable performance I don't think anything short of LN2 could keep it cool enough to sustain it.

RDNA4 is a pretty good as is, but people expecting miracles will likely be disappointed. Even ignoring the cores, there's the smaller memory bus and infinity cache. The expected die size for Navi 44 is ~150 mm^2.

There are too many constraints for a 9060 XT to match the 7700 XT in my opinion. Not that it really matters. If a 9060 XT gives you 16 GB and 90% of the performance at $300 it's an amazing card even if it's not as good as a 7700 XT. I think people are losing sight of that aspect.

jpiniero · Apr 18, 2025

Mopetar said:
There are too many constraints for a 9060 XT to match the 7700 XT in my opinion. Not that it really matters. If a 9060 XT gives you 16 GB and 90% of the performance at $300 it's an amazing card even if it's not as good as a 7700 XT. I think people are losing sight of that aspect.

It's not going to be $300. Expect $400.

Timorous · Apr 18, 2025

Mopetar said:
I'm not sure that's the case. When you get to the high end of the silicon the power use starts to scale as a cube function as the voltage increase necessary for frequency increase becomes linear.

Even if the silicon were capable of the clock speeds necessary to give comparable performance I don't think anything short of LN2 could keep it cool enough to sustain it.

RDNA4 is a pretty good as is, but people expecting miracles will likely be disappointed. Even ignoring the cores, there's the smaller memory bus and infinity cache. The expected die size for Navi 44 is ~150 mm^2.

There are too many constraints for a 9060 XT to match the 7700 XT in my opinion. Not that it really matters. If a 9060 XT gives you 16 GB and 90% of the performance at $300 it's an amazing card even if it's not as good as a 7700 XT. I think people are losing sight of that aspect.

Let's compare the 7900GRE with 80CUs at 2.3Ghz to the 7600XT with 32CUs at 2.7Ghz. Fundamentally the 7600XT has half the compute, bandwidth and infinity cache of the 7900GRE and performance is about 55% of the GRE.

From what we know the 9060XT is going to be similar relative to the 9070XT. Half the CUs, half the infinity cache and half the bandwidth. It looks to have a 10% clock speed boost so it's performance delta to the 9070XT should be a little better than the 7600XTs is to the 7900GRE.

55% of a 9070XT is 90% of a 7700XT but that is a lower bound because the raw compute of the 9060XT seems to be closer to the 9070XT than the 7600XT was to the 7900GRE.

As for price, I can see $350 because it is essentially half the 9070XT bar the Vram and $350 is probably enough to keep the margins similar to the 9070XT while keeping the per/$ in the same ballpark.

coercitiv · Apr 19, 2025

jpiniero said:
It's not going to be $300. Expect $400.

Makes sense, the idea is to upsell you to 5060 TI 16GB

TESKATLIPOKA · Apr 19, 2025

Mopetar said:
I think that's obvious which is also why I don't think it will hit 7700 XT performance levels.

And why do you think at 200W It won't clock >3GHz?
Average GPU clock for 9070XT after OC -> limit 404W max.

Mopetar said:
Even 200W is more than this should ever draw.

7600XT had 190W TDP while 7800XT had only 263W. If they need the extra performance then 200W is quite possible.

Mopetar said:
The estimated die size for Navi 44 is around 150 mm^2.

I don't know where you heard that N44 will be only ~150mm2, but N48 is 356.5mm2.
175-185mm2 would be already very good.

Mopetar said:
Cooling it becomes more of an issue than powering it at a certain point.

This shouldn't be an issue considering It is very likely not ~150mm2.

Vikv1918 · Apr 19, 2025

Anyone know what this livestream from AMD Gaming youtube channel is about?

Starting Apr 22. Is this the 9060 XT announcement?

Thunder 57 · Apr 19, 2025

Vikv1918 said:
Anyone know what this livestream from AMD Gaming youtube channel is about?

Starting Apr 22. Is this the 9060 XT announcement?

From rumors only days ago I thought no. But it sure looks like it. Especially if it is launching at Computex.

jpiniero · Apr 19, 2025

coercitiv said:
Makes sense, the idea is to upsell you to 5060 TI 16GB

They could always do the Fake MSRP thing... but the Real MSRP of the 5060 Ti 16 GB is $479.

marees · Apr 19, 2025

jpiniero said:
They could always do the Fake MSRP thing... but the Real MSRP of the 5060 Ti 16 GB is $479.

My expectation is that 9070 gre will not get a worldwide release until prices settle down & fake msrp = real msrp (=$400?)

Discussion RDNA4 + CDNA3 Architectures Thread

Golden Member

Golden Member

Diamond Member

Golden Member

Platinum Member

Diamond Member

Diamond Member

Diamond Member

Diamond Member

Diamond Member

Diamond Member

Diamond Member

Diamond Member

Diamond Member

Diamond Member

Diamond Member

Member

Diamond Member

Lifer

Golden Member

Diamond Member

Platinum Member

Junior Member

Diamond Member

Lifer

Golden Member