Question Speculation: RDNA3 + CDNA2 Architectures Thread

[uzzi38]

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 is much bigger than from RDNA1 to RDNA2. We should expect many big improvements in GFX11. 🤔" / Twitter

 

[Timorous]

Problem is that 16GB is an overkill for this level of performance.
12GB would have been better, but that can't be used with 128-bit bus.

BTW, AMD asked only $20 more for extra 4GB with RX 6500XT 8GB.

Sure but it is not like 16GB won't get used better looking textures with less LOD pop can make a huge difference in IQ and it does not really cost performance.

12 GB would be more balanced of course but as you say, without using a wonky config it is 8GB or 16GB.

We had this discussion with the RX480 4GB vs 8GB. the 8GB was the better buy by far for people who keep their GPUs a while and I suspect this will be the same.

a 200mm N6 chip is going to be dirt cheap to make long term so I would not be surprised if this gets an RDNA 3.5 refresh in the form of a 7650XT or possibly an 8500XT if RDNA 4 launches this year.

I expect this will be the RX580 of the generation, especially when it drops below $250 which I suspect it will eventually.

 

[Glo.]

Problem is that 16GB is an overkill for this level of performance.
12GB would have been better, but that can't be used with 128-bit bus.

BTW, AMD asked only $20 more for extra 4GB with RX 6500XT 8GB.

Not overkill if it targeted at LLMs. As a cheap, budget entry option for AI.

BTW. Don't expect that GDDR7 will lower prices on this front. It comes in 2x capacities, and starts with 16 Gb chips. So expect that if currently we pay 4$/GB with GDDR7 we will be paying 10$/GB at the start.

And 12 GB VRAM will costs 120$. You guys know should know what I am pointing at.

 

[DeathReborn]

Problem is that 16GB is an overkill for this level of performance.
12GB would have been better, but that can't be used with 128-bit bus.

BTW, AMD asked only $20 more for extra 4GB with RX 6500XT 8GB.

Technically you can have 12GB on a 128bit bus, it's just not great for performance. 4x 2GB & 4x 1GB chips.

 

[TESKATLIPOKA]

I expect this will be the RX580 of the generation, especially when it drops below $250 which I suspect it will eventually.

I beg to differ.
Both RX 480 and RX 580 cost less than this, but every card now is costlier so this is not that important.
But both of them offered a lot more performance in comparison.
4K TPU
RX 480 vs GTX 1080 -> 100% vs 184%
RX 580 vs GTX 1080Ti -> 100% vs 213%
RX 7600 vs RTX 4090 -> 100% vs 392%

 

[TESKATLIPOKA]

Technically you can have 12GB on a 128bit bus, it's just not great for performance. 4x 2GB & 4x 1GB chips.

I don't think this config would have an impact on performance, because you still access 128-bit.

 

[Heartbreaker]

I don't think this config would have an impact on performance, because you still access 128-bit.

The channels are unbalanced. Your extra 4GB are only on 64 bits of bus, so access speed to that extra 4GB would be at half the bandwidth, of the first 8GB.

This is why you never see this configuration.

 

[Timorous]

I beg to differ.
Both RX 480 and RX 580 cost less than this, but every card now is costlier so this is not that important.
But both of them offered a lot more performance in comparison.
4K TPU
RX 480 vs GTX 1080 -> 100% vs 184%
RX 580 vs GTX 1080Ti -> 100% vs 213%
RX 7600 vs RTX 4090 -> 100% vs 392%

RX580 - $229. 1080Ti $699. 3.05x more.

7600XT - $329. 4090 $1,599. 4.86x more.

329 * 3.05 = 1003 so around 7900XTX MSRP.

7900XTX at TPU 4K is 311% ahead of 7600 although at 4K with 8GB of VRAM you are going to be hitting some performance issues due to lack of VRAM which is not something that is as visible with the RX580/1080Ti or RX480 8GB / 1080Ti 4K data since back then 8GB was plenty. It is shame they don't have 480 4GB data because at 4K that would be the ideal comparitor and would be more similar.

NV don't have a direct price point competitor although if you had a card that was perfectly between 4070Ti and 4080 for $1,000 then that would be 271% at 4K.

At 1440p where 8GB won't be as much of an issue the 7900XTX is 256% and the NV scaled part would be 230%.

This also presumes 7600XT and 7600 performance is the same and it looks as though the XT will be a bit faster bringing these deltas down.

I still think $329 is a bit too much and $299 would be far better, that would make it pretty much the RX580 replacement in terms of price/perf vs higher tier parts as well as having a VRAM buffer that will allow it to perform decently well for a while. I suspect it will drop to $299 relatively quickly.

 

[TESKATLIPOKA]

The channels are unbalanced. Your extra 4GB are only on 64 bits of bus, so access speed to that extra 4GB would be at half the bandwidth, of the first 8GB.

This is why you never see this configuration.

Are not, because there are 4 x 1GB chips. What you wrote would be true, if there were 4x 2GB chips on one side and 2x 2GB on the other.

 

[Heartbreaker]

Are not, because there are 4 x 1GB chips. What you wrote would be true, if there were 4x 2GB chips on one side and 2x 2GB on the other.

Then why do you think we NEVER see this config? It would make sense for both 4060 Ti and 7600 XT to be 12GB cards rather than 16 GB just so the don't stand out in the lineup having more VRAM than the model above, if it would just work without issue.

There is likely still an addressing snag in there.

 

[MrTeal]

Are not, because there are 4 x 1GB chips. What you wrote would be true, if there were 4x 2GB chips on one side and 2x 2GB on the other.

So with four 32bit interfaces you'd run a 2GB and a 1GB chip clamshell? I'd imagine for a low cost product they'd probably want to stay away from that.

 

[MrTeal]

Not overkill if it targeted at LLMs. As a cheap, budget entry option for AI.

BTW. Don't expect that GDDR7 will lower prices on this front. It comes in 2x capacities, and starts with 16 Gb chips. So expect that if currently we pay 4$/GB with GDDR7 we will be paying 10$/GB at the start.

And 12 GB VRAM will costs 120$. You guys know should know what I am pointing at.

Do you have a source for that? DRAM Exchange shows GDDR6 spot price as $3.09/GB average for the session, and generally contract prices at slightly lower than that.

 

[TESKATLIPOKA]

RX580 - $229. 1080Ti $699. 3.05x more.

7600XT - $329. 4090 $1,599. 4.86x more.

329 * 3.05 = 1003 so around 7900XTX MSRP.

7900XTX at TPU 4K is 311% ahead of 7600 although at 4K with 8GB of VRAM you are going to be hitting some performance issues due to lack of VRAM which is not something that is as visible with the RX580/1080Ti or RX480 8GB / 1080Ti 4K data since back then 8GB was plenty. It is shame they don't have 480 4GB data because at 4K that would be the ideal comparitor and would be more similar.

NV don't have a direct price point competitor although if you had a card that was perfectly between 4070Ti and 4080 for $1,000 then that would be 271% at 4K.

At 1440p where 8GB won't be as much of an issue the 7900XTX is 256% and the NV scaled part would be 230%.

This also presumes 7600XT and 7600 performance is the same and it looks as though the XT will be a bit faster bringing these deltas down.

I still think $329 is a bit too much and $299 would be far better, that would make it pretty much the RX580 replacement in terms of price/perf vs higher tier parts as well as having a VRAM buffer that will allow it to perform decently well for a while. I suspect it will drop to $299 relatively quickly.

7600XT is only ~2x faster than RX 580. You can hardly expect It to offer the same FPS in 2029 as does RX 580 offer today.
BTW, let's not forget that this 7600XT has totally useless RT performance even now let alone later.
If someone wants to buy this card as a RX 580 replacement or use It that long, then I pity him.

P.S. If I had to buy a card within the next 2 months, then to me RTX 4070 TI Super looks like the best allrounder.

edit: @Thunder 57 or you are right, that I should have chosen a different card against 7600 than RTX 4090.

 

[TESKATLIPOKA]

Then why do you think we NEVER see this config? It would make sense for both 4060 Ti and 7600 XT to be 12GB cards rather than 16 GB just so the don't stand out in the lineup having more VRAM than the model above, if it would just work without issue.

There is likely still an addressing snag in there.

Because price between 8Gbit and 16gbit is so low? Just a guess.
I don't see what would be the problem with addressing? If It's in clamshell, isn't It like 4GB instead of 2GB in case of this 7600XT? What issue could be there?

 

[TESKATLIPOKA]

So with four 32bit interfaces you'd run a 2GB and a 1GB chip clamshell? I'd imagine for a low cost product they'd probably want to stay away from that.

Yet they are doing exactly the same thing with 7600XT 16GB. 8x 16gbit chips in clamshell.

 

[Thunder 57]

7600XT is only ~2x faster than RX 580. You can hardly expect It to offer the same FPS in 2029 as does RX 580 offer today.
BTW, let's not forget that this 7600XT has totally useless RT performance even now let alone later.
If someone wants to buy this card as a RX 580 replacement or use It that long, then I pity him.

P.S. If I had to buy a card within the next 2 months, then to me RTX 4070 TI Super looks like the best allrounder.

You're missing the point. You made a nonsensical argument about performance of the RX 480/580 vs the 1080/1080 Ti. Then compared that with a 7600 vs 4090. The 1080/Ti MSRP was $599/$699. The MSRP of the 4090 is $1599. Which one of these is not like the other?

Of course, you already knew that. You know what you were doing. I mean, if the 7600 cost $1000 more than the 480/580, I'd hope it would perform way better. But no, it's $30 more.

 

[jpiniero]

Do you have a source for that? DRAM Exchange shows GDDR6 spot price as $3.09/GB average for the session, and generally contract prices at slightly lower than that.

It's not per GB, it's for a 1 GB chip. And it's at an unknown speed, probably 14 gbps. The only product still on the market using 1 GB chips is the Series X (lol), and who knows how much inventory Microsoft has on that. The only demand for 1 GB chips otherwise is for warranty replacements I would have to think.

 

[TESKATLIPOKA]

You're missing the point. You made a nonsensical argument about performance of the RX 480/580 vs the 1080/1080 Ti. Then compared that with a 7600 vs 4090. The 1080/Ti MSRP was $599/$699. The MSRP of the 4090 is $1599. Which one of these is not like the other?

Of course, you already knew that. You know what you were doing. I mean, if the 7600 cost $1000 more than the 480/580, I'd hope it would perform way better. But no, it's $30 more.

It's not only $30 more.
RX480/580 4GB $199 USD vs RX 7600 8GB $269 (+$70 or +35%)
RX480/580 8GB $229/239 USD vs RX 7600 XT 16GB $329 (+$90-100 or +38-44%)

My point was that RX 580 was more performant vs TOP dog of that time than RX 7600XT is against RTX 4090.
You are right, that price difference between them is not comparable, so maybe I should have chosen something else against 7600, but what I wanted to say was that RX 7600XT most likely won't perform after 5 years like RX 580 does today in comparison, because It's practically a lower tier card than RX 580 was.
So I don't consider It as a RX 580 of this generation or Its successor.

 

[Timorous]

7600XT is only ~2x faster than RX 580. You can hardly expect It to offer the same FPS in 2029 as does RX 580 offer today.
BTW, let's not forget that this 7600XT has totally useless RT performance even now let alone later.
If someone wants to buy this card as a RX 580 replacement or use It that long, then I pity him.

P.S. If I had to buy a card within the next 2 months, then to me RTX 4070 TI Super looks like the best allrounder.

RT is not that big a deal at this low end IMO. It needs upscaling and frame gen tricks to be playable with this tier of cards and then you are sacrificing a lot of IQ just to turn it on and usually it is a tradeoff not worth making.

The 4070Ti Super is going to be what $800? Not exactly entry level is it.

 

[Timorous]

It's not only $30 more.
RX480/580 4GB $199 USD vs RX 7600 8GB $269 (+$70 or +35%)
RX480/580 8GB $229/239 USD vs RX 7600 XT 16GB $329 (+$90-100 or +38-44%)

My point was that RX 580 was more performant vs TOP dog of that time than RX 7600XT is against RTX 4090.
You are right, that price difference between them is not comparable, so maybe I should have chosen something else against 7600, but what I wanted to say was that RX 7600XT most likely won't perform after 5 years like RX 580 does today in comparison, because It's practically a lower tier card than RX 580 was.
So I don't consider It as a RX 580 of this generation or Its successor.

1080TI SLI would have been top dog then and similar money to the 4090. If 1080Ti scaled like the 1080 SLI did then that is about + 50% performance in the TPU average putting it around 310% ahead of the RX 580 and a lot more in cases where SLI scaled really well.

 

[TESKATLIPOKA]

RT is not that big a deal at this low end IMO. It needs upscaling and frame gen tricks to be playable with this tier of cards and then you are sacrificing a lot of IQ just to turn it on and usually it is a tradeoff not worth making.

RT is not really worth the performance penalty, true, but It should improve image quality, that's why I mentioned It.
If you don't use It, then you are playing at correct settings.

The 4070Ti Super is going to be what $800? Not exactly entry level is it.

Certainly not entry level, I wouldn't even invest that much into a GPU, but at least It should be usable for some time.

 

[Thunder 57]

It's not only $30 more.
RX480/580 4GB $199 USD vs RX 7600 8GB $269 (+$70 or +35%)
RX480/580 8GB $229/239 USD vs RX 7600 XT 16GB $329 (+$90-100 or +38-44%)

My point was that RX 580 was more performant vs TOP dog of that time than RX 7600XT is against RTX 4090.
You are right, that price difference between them is not comparable, so maybe I should have chosen something else against 7600, but what I wanted to say was that RX 7600XT most likely won't perform after 5 years like RX 580 does today in comparison, because It's practically a lower tier card than RX 580 was.
So I don't consider It as a RX 580 of this generation or Its successor.

Was a price announced on the 7600XT? I read it was rumored to be $300. Either way I wouldn't touch that. I was trying to compare the RX 480/580 8GB to the 7600. Yes, 8GB isn't great today (unless you play at the right settings), but as you mentioned the 480/580 were mid range cards whereas the 7600 is entry level. I think it's OK with 8GB, but no way do I see it aging like Polaris.

 

[TESKATLIPOKA]

1080TI SLI would have been top dog then and similar money to the 4090. If 1080Ti scaled like the 1080 SLI did then that is about + 50% performance in the TPU average putting it around 310% ahead of the RX 580 and a lot more in cases where SLI scaled really well.

I totally forgot about It. Yes, 1080Ti still has the SLI connector.

 

[Thunder 57]

1080TI SLI would have been top dog then and similar money to the 4090. If 1080Ti scaled like the 1080 SLI did then that is about + 50% performance in the TPU average putting it around 310% ahead of the RX 580 and a lot more in cases where SLI scaled really well.

SLI/Crossfire was almost always a gimmick that was more trouble than it was worth. It was also dead even if supported by the 1080 era.

 

[jpiniero]

Was a price announced on the 7600XT?

$329

 

[TESKATLIPOKA]

1080TI SLI would have been top dog then and similar money to the 4090. If 1080Ti scaled like the 1080 SLI did then that is about + 50% performance in the TPU average putting it around 310% ahead of the RX 580 and a lot more in cases where SLI scaled really well.

I totally forgot about It. Yes, 1080Ti still had the SLI connector.

Was a price announced on the 7600XT? I read it was rumored to be $300. Either way I wouldn't touch that. I was trying to compare the RX 480/580 8GB to the 7600. Yes, 8GB isn't great today (unless you play at the right settings), but as you mentioned the 480/580 were mid range cards whereas the 7600 is entry level. I think it's OK with 8GB, but no way do I see it aging like Polaris.

$329 supposedly. @jpiniero was faster.
Thanks for saying what I wanted to say.