Question Speculation: RDNA3 + CDNA2 Architectures Thread

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uzzi38

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TESKATLIPOKA

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Sapphire begs to differ.

:)
Wow, didn't know about that, thanks for posting.
I just checked and It can be bought in my country for 294,90€, which is 53€ more than the 4GB Sapphire pulse version. Sadly, I couldn't find a review for It to see If It's worth the extra cost or not.

Edit: Sapphire Pulse RX 6600 8GB costs only 324,38 €, so 6500XT is definitely not worth It. Doesn't matter If It's 4 or 8GB version.
 
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Saylick

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Not really new news if you've been following this thread, but more evidence that the 7900 series is all N31 with the 7900XT being the cut-down N31 w/ 20GB VRAM and the 7950XT being the full N31 w/ 24 GB VRAM.

Still no confirmation on performance targets.

 

RnR_au

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Glo.

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I don't think we will see N31 in laptops.
N32 is the safe bet, but maybe N33 will surprise us with Its performance at 1080p.
If he meant with RT then It is N33, because RDNA2 is so bad in It.
The majority is N33. I don't know about N32, but based on the rumored scaling: 10754 RDNA3 ALUs are needed to tie, or beat RTX 4090 on desktop, then I'd assume that indeed N32 in laptop form is around 6950XT desktop performance.

Not bad.

P.S. Doesn't it make it 100% 4k@120 FPS capable...?
 
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TESKATLIPOKA

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The majority is N33. I don't know about N32, but based on the rumored scaling: 10754 RDNA3 ALUs are needed to tie, or beat RTX 4090 on desktop, then I'd assume that indeed N32 in laptop form is around 6950XT desktop performance.

Not bad.

P.S. Doesn't it make it 100% 4k@120 FPS capable...?
If It's the full N32 at 150W then It's not so great considering He also claimed N33 was close to RX 6900XT, even If only at 1080p and desktop N33 supposedly consumes <170W.
 
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GodisanAtheist

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IF AMD is dropping super efficient / low power cards on us then it means that the performance has to be competitive with what NV is posting up.

Otherwise we'd be hearing "falling short of their efficiency gain/power targets" as AMD crushes the curve to squeeze out every last drop of performance and close the gap.
 
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TESKATLIPOKA

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He also said 150W +/- so that is more than 2x the perf/watt if true. 150W makes me think low clocked cut down version as well.
We still compare a Laptop model vs Desktop model.
For example RX 6800M has ~45-50% better perf/W compared to desktop model.
Gaming FrequencyTBPSpecification
RX 6700 XT2424 MHz230 W40CU; 192bit 16gbps
RX 6800M2300 MHz145+ W40CU; 192bit 16gbps
Screenshot_1.png
6700XT is only 5% faster in Cyberpunk 2077 than 6800M and RX 6900XT is 76% faster.
So this N32 will provide ~80% higher performance at ISO power(150W) than N22. If It's actually a cutdown model that would be even better, but I wouldn't bet on It.
 

Timorous

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We still compare a Laptop model vs Desktop model.
For example RX 6800M has ~45-50% better perf/W compared to desktop model.
Gaming FrequencyTBPSpecification
RX 6700 XT2424 MHz230 W40CU; 192bit 16gbps
RX 6800M2300 MHz145+ W40CU; 192bit 16gbps
View attachment 69623
6700XT is only 5% faster in Cyberpunk 2077 than 6800M and RX 6900XT is 76% faster.
So this N32 will provide ~80% higher performance at ISO power(150W) than N22. If It's actually a cutdown model that would be even better, but I wouldn't bet on It.

The 6700XT is a bit of an outlier because AMD just pushed the desktop part to its limits.

Since 6800M was a lower clocked 6700XT it is not far fetched to think 7800M will be a lower clocked 7700XT.
 
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TESKATLIPOKA

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The 6700XT is a bit of an outlier because AMD just pushed the desktop part to its limits.

Since 6800M was a lower clocked 6700XT it is not far fetched to think 7800M will be a lower clocked 7700XT.
Difference in gaming frequency is only 5% so 6800M is also pushed very high.
This just shows how much better a binned chip can be.

Now let's go back to greymon55's leak.
I have to wonder how high is this N32 actually clocked, because 80% higher performance at ISO power is not so much If I think about N32's specs.
N32 has 50% more WGPs than N22(30 vs 20) and each WGP should be significantly better.

Expected performance per ISO power(~150W)
RX 6800M : 100%
N32 mobile : +80%

N32 has +50% WGPs and If we say RDNA 3 WGP is 50% better than RDNA2 WGP then ideally that's 100*1.5*1.5=225% or +125% higher performance, but It's actually only +80%. I have to lower clockspeed by 20% from 2300MHz to 1840MHz to have the expected performance.

This leak from Greymom55 could actually be a cutdown version of N32, because I don't expect a mobile N32 to be downclocked from >3GHz down to <2GHz just to be within 145-165W, when N22 was downclocked by only a few %.
 
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Kaluan

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Sapphire begs to differ.

:)

For anyone interested, I finally found someone testing (Sapphire's) 6500 XT 8GB performance, it's hidden in this Arc A380 review:

6500XT 8GB 5.jpg

And a few other more uncommon/older/light games tested, with those the difference is predictably smaller.
Testbed is Ryzen 5 3600X, B550 and 2x8GB DDR4-3200.

Now, looping back to N33 and discussions of 8x lane being a weakness, and similarly that 4x was the 6500 XT's biggest weakness, where I said I don't think that's true, the 4GB VRAM, in tandem with 4x lanes and too little effective bandwidth (144GB + 16MB IC) made a deadly performance-killing/stutter fest combo. Glad to see a proper frame buffer size fixed most of that and then some.
With the supposed end-to-end compression RDNA3 has, penalties for going more often out of VRAM and back would be lessen on a 4x, 4GB 6500XT, if it was hypoethically RDNA3 uArch.

There's no 3.0 vs 4.0 tests (this isn't a 6500 XT 8GB review after all), but I think we'd see an even wider gap between 4GB and 8GB.

Back when Sapphire's 6500 XT 8GB was announced, there were many saying so much VRAM is a waste and N24 can't make use of it lol

That being said, I am curious what will the eventual RX 7500/7400 family be based off... Cut down N33? Later announced N34 (similar to how N24 was only discovered much later)? N23 N6 refresh? And will AMD not mess up it's entry lineup again like that?
 

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Timorous

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For anyone interested, I finally found someone testing (Sapphire's) 6500 XT 8GB performance, it's hidden in this Arc A380 review:

View attachment 69633

And a few other more uncommon/older/light games tested, with those the difference is predictably smaller.
Testbed is Ryzen 5 3600X, B550 and 2x8GB DDR4-3200.

Now, looping back to N33 and discussions of 8x lane being a weakness, and similarly that 4x was the 6500 XT's biggest weakness, where I said I don't think that's true, the 4GB VRAM, in tandem with 4x lanes and too little effective bandwidth (144GB + 16MB IC) made a deadly performance-killing/stutter fest combo. Glad to see a proper frame buffer size fixed most of that and then some.
With the supposed end-to-end compression RDNA3 has, penalties for going more often out of VRAM and back would be lessen on a 4x, 4GB 6500XT, if it was hypoethically RDNA3 uArch.

There's no 3.0 vs 4.0 tests (this isn't a 6500 XT 8GB review after all), but I think we'd see an even wider gap between 4GB and 8GB.

Back when Sapphire's 6500 XT 8GB was announced, there were many saying so much VRAM is a waste and N24 can't make use of it lol

That being said, I am curious what will the eventual RX 7500/7400 family be based off... Cut down N33? Later announced N34 (similar to how N24 was only discovered much later)? N23 N6 refresh? And will AMD not mess up it's entry lineup again like that?

I think 7500 will be cut N33 with 6GB.

Below that not sure, APU perhaps or maybe there will be an N34 at some point.