Question Speculation: RDNA2 + CDNA Architectures thread

[uzzi38]

All die sizes are within 5mm^2. The poster here has been right on some things in the past afaik, and to his credit was the first to saying 505mm^2 for Navi21, which other people have backed up. Even still though, take the following with a pich of salt.

Navi21 - 505mm^2

Navi22 - 340mm^2

Navi23 - 240mm^2

Source is the following post: https://www.ptt.cc/bbs/PC_Shopping/M.1588075782.A.C1E.html

 

[Glo.]

Navi 23 - RTX 2080 Super performance levels +10%, @150W TBP.
Navi 22 - 10-20% above RTX 2080 Ti performance levels @225 TBP.
Navi 21 - 40-50% above RTX 2080 Ti performance @ 275W TBP.

Those were performance targets for RDNA2, that I got hint few weeks ago.

 

[lobz]

In reply to the discussion in the Ampere thread

While I wouldn't really like to see a highly competitive card from AMD I'm also careful to let expectations run away.

I made some really low quality napkin calculations that I myself at least find interesting enough to post.

According to techpowerup RDNA1 stacks up @ 4K:

GPU	Perf compared to 5700 XT	TDP	Mem-Bus width	Memory Bandwidth
2060	83%	160W *	192 bit	336.0 GB/s
5700	88%	180W	256 bit	448.0 GB/s
2070 (vanilla)	100%	175W	256 bit	448.0 GB/s
5700XT	100%	225W	256 bit	448.0 GB/s
2070 Super	114%	175W *	256 bit	448.0 GB/s
2080 Ti	156%	250W *	352 bit	616.0 GB/s
Hyphothetical 6800 XT (roughly 5700 clocks/IPC)	~165% (@ around 93% scaling)	~300W?	512 bit? **	896 GB/s ? **
Hyphothetical 6800 XT (@2.0 Ghz 5700 as baseline)	~190% (same scaling)	~300W?	512 bit? **	896 GB/s ? **
Hyphotetical 6800 XT (@2.0 Ghz 5700 XT as baseline)	~ 203%	???	512 bit? **	896 GB/s ? **
Hypotetical 3090 (low bar)	~202%? (130% of 2080 Ti ***)	350W?	352 bit (GDDR6X)	1008.0 GB/s
Hypotetical 3090 (still nothing exceptional)	~ 234%? (150% of 2080 Ti ***)	350W?	352 bit (GDDR6X)	1008.0 GB/s

* Yes AMD and Nvidia TDP are a bit apples to oranges but similar enough to do these on-the-napkin comparisons. Overall 2070 vanilla has very similar shader resources and TDP as 5700 and 2070 Super is about as wide as 5700XT, yet Nvidia performs 10-15% better.

** I'm still a little sceptical of the 512 bit mem-bus rumors for GDDR6 (though 16GB of VRAM heavily points in the direction) considering the die-size. Otherwise I would have guessed 384 - 448 bit GDDR6. Given the leaks though let's assume this is true. From Linux driver leaks we know that the initial versions will be GDDR6 with HBM2(E?) Pro versions coming early next-year.

*** This looks like a really estimation considering 1.3x the perfomance with 1.4x the TDP at a full-node-shrink. This is an absolute worst case AMD could possibly have projected when starting design of Navi 21, with 150-170% of 2080 Ti being the more pessimistic/probable result (especially if nvidia were still to use 7nm).

A couple of points from the Table:

1. 2080 Ti is pretty close to 2x 2060 (some units slightly less, some more) so it's a good comparison for a would-be 80CU 512bit bus RDNA2 (s 5700/5700 XT). It doesn't quite double up but gets a nice 93% scaling. I based the RDNA2 scaling on the result. It's also interesting to note that doubling pretty much everything did not double the TDP, not even close.
2. If AMD pulls a hail-mary and doubles up on 5700Xt (not an easy task @ 300W), it still wouldn't quite reach a hypothetical 3090 with a 40-50% perf-increase on top of 2080 Ti. It can only be in it's territory if Nvidia failed miserably and managed only a unprecedentedly bad 30% perf-gain for 40% TPD increase in 2 years and a full node shrink.
3. Now one could go to 2.1-2.2 Ghz but I'm really sceptical of that. I can see them hitting these clocks with mid-range ~40-50CU cards but not with ultra wide memory bus flagship. I also don't believe in huge IPC gains as Microsoft in their Xbox presentation listid the same IPC growth for RDNA2 (from polaris) that AMD listed for RDNA1 (from Vega). It shouldn't be more than a couple of percent.

As a side note I personally hope AMD does release a HBM2E version for consumers as well and that they also released a water-cooled flagship model (that seems to be case from linux-driver leaks). Those should be able to extract a little more perf.

Conclusion

Anyway feel free to disagree/argue or shoot it all down. I just putting some numbers into a context as to what I personally find likely - a rosy but not totally unplausible result.

My point being: expecting anything more seems like getting fully on board of the hype-train (r/AMD level). Doesn't mean it's totally impossible, rather exceedingly more unlikely. I can also easly see AMD unable to pull this off and ending up at 150-160% scaling (that is what Coretex predicted)

Have you used google translate to post this? I really don't want to be rude, but I'm just probably old because I'm having a hard time decoding half of it.

 

[Gideon]

Navi 23 - RTX 2080 Super performance levels +10%, @150W TBP.
Navi 22 - 10-20% above RTX 2080 Ti performance levels @225 TBP.
Navi 21 - 40-50% above RTX 2080 Ti performance @ 275W TBP.

Those were performance targets for RDNA2, that I got hint few weeks ago.

That would indeed be an unprecedented increase in performance. A total "Zen 1" moment for AMD GPUs if you will.

I can only hope that's true

 

[Glo.]

That would indeed be an unprecedented increase in performance. A total "Zen 1" moment for AMD GPUs if you will.

I can only hope that's true

Dude. How come?

AMD promised 50% perf/watt uplift over RDNA1. Navi 23, 40 CU GPU, with 256 bit memory bus, and performance 10% above RTX 2080 Super IS JUST, EXACTLY THAT.

Nobody has been paying attention to their execution, lately, huh?

 

[moinmoin]

Nobody has been paying attention to their execution, lately, huh?

AMD used up their luck for executing their CPUs so well, it's obvious there's nothing left for the GPUs! /s

 

[Gideon]

Have you used google translate to post this? I really don't want to be rude, but I'm just probably old because I'm having a hard time decoding half of it.

No, but I did write it @ 3 a.m. redacting it constantly and trying to cram way too much info into it (while making countless typos).

I tried cleaning it up a bit. Hopefully makes more sense now

 

[Gideon]

Dude. How come?

AMD promised 50% perf/watt uplift over RDNA1. Navi 23, 40 CU GPU, with 256 bit memory bus, and performance 10% above RTX 2080 Super IS JUST, EXACTLY THAT.

Nobody has been paying attention to their execution, lately, huh?

Yeah. Like I said, I really hope this is true and sure-enough Xbox Series X and PS5 seem to hint at the possibility.

It's just that I've been burned by their claims way too many times before. Take this this polaris slide for example. Plenty of Vega marketing material was similar. Anyone here still remembers the 20% better throughput claim of Bulldozer vs Phenom?

But let's not get bogged down in the past. RDNA2 looked to be a really strong product, If what you rumored is true, It's outstanding.

 

[JasonLD]

Estimating target performance just by looking at perf/w improvement claim just isn't going to work without knowing what is being compared.
If you look at 2080 Super vs 2080ti, their power consumption difference is very small, which would make 2080ti quite a bit ahead vs 2080 super in terms of perf/w.

 

[Stuka87]

Estimating target performance just by looking at perf/w improvement claim just isn't going to work without knowing what is being compared.
If you look at 2080 Super vs 2080ti, their power consumption difference is very small, which would make 2080ti quite a bit ahead vs 2080 super in terms of perf/w.

2080 S and 2080Ti have nearly identical Perf:Watt.

AMD's statement that RDNA 2 will have a 50% increase is based on what they had for RDNA 1. This would make Navi 10's successor 16% faster than 2080Ti at the same wattage of the 5700 XT. The 5700 XT of course is a made range chip. So if AMD has a 300W chip, that could in theory, make it very competitive with what the 3090 is looking like, only at a smaller power footprint.

 

[JasonLD]

2080 S and 2080Ti have nearly identical Perf:Watt.

AMD's statement that RDNA 2 will have a 50% increase is based on what they had for RDNA 1. This would make Navi 10's successor 16% faster than 2080Ti at the same wattage of the 5700 XT. The 5700 XT of course is a made range chip. So if AMD has a 300W chip, that could in theory, make it very competitive with what the 3090 is looking like, only at a smaller power footprint.

Ah, performance/w gap was too small between 2080 Super and 2080ti. 2080Ti did have a better perf/w for most benchmarks I saw on Perf/w, but it was around 4-5% at best. I think better example would be 5700 vs 5700XT, where perf/w gap was larger.
I still think perf/w isn't the best measuring stick to predict how the top performing part would end up, to the point of claiming over 200% improvement from 5700Xt. I guess we will see and find out.

 

[Stuka87]

Ah, performance/w gap was too small between 2080 Super and 2080ti. 2080Ti did have a better perf/w for most benchmarks I saw on Perf/w, but it was around 4-5% at best. I think better example would be 5700 vs 5700XT, where perf/w gap was larger.
I still think perf/w isn't the best measuring stick to predict how the top performing part would end up, to the point of claiming over 200% improvement from 5700Xt. I guess we will see and find out.

The 5700 XT's replacement wont be 200% faster. But the 5700 XT was a mid tier chip. This time around AMD should have a top tier competitor. If that is true, 200% faster should be very possible.

 

[trexfromouterspace]

The 5700 XT's replacement wont be 200% faster. But the 5700 XT was a mid tier chip. This time around AMD should have a top tier competitor. In that is true, 200% faster should be very possible.

No, we're getting an RTX 3090 killer for $400. Get with the program.

 

[exquisitechar]

Navi 23 - RTX 2080 Super performance levels +10%, @150W TBP.
Navi 22 - 10-20% above RTX 2080 Ti performance levels @225 TBP.
Navi 21 - 40-50% above RTX 2080 Ti performance @ 275W TBP.

Those were performance targets for RDNA2, that I got hint few weeks ago.

N22 performance makes little sense according to this. An N23 based card, with 40CUs, is pretty close to 2080ti performance or a bit below depending on the resolution if it’s 2080S+10%. N22, with a rumored 60CUs, is only 10-20% above that?

You’re overestimating N23, IMO. It won’t reach that performance with just 40CUs, absolutely not with a 150W TBP.

 

[leoneazzurro]

N22 performance makes little sense according to this. An N23 based card, with 40CUs, is pretty close to 2080ti performance or a bit below depending on the resolution if it’s 2080S+10%. N22, with a rumored 60CUs, is only 10-20% above that?

You’re overestimating N23, IMO. It won’t reach that performance with just 40CUs, absolutely not with a 150W TBP.

Not that I love performance estimates based on rumors, but for the sake of precision in Glo's listing N23 was compared to 2080 Super, N22 to 2080 Ti, between the two there is another 10-30% depending on the game, which should be added to the listed number for the difference between N22 and N23 (using an average of 20%, N23 should be 30-40% slower than N22, based on that list).

 

[exquisitechar]

Not that I love performance estimates based on rumors, but for the sake of precision in Glo's listing N23 was compared to 2080 Super, N22 to 2080 Ti, between the two there is another 10-30% depending on the game, which should be added to the listed number for the difference between N22 and N23 (using an average of 20%, N23 should be 30-40% slower than N22, based on that list).

According to computerbase, 2080ti FE is about 1.08x Glo’s predicted N23 performance (using 2080S FE*1.1) at 1440p. So N22 would be around the range of 1.19-1.29x N23 performance. Seems unlikely with 1.5x the TBP and 1.5x the CUs.

 

[Gideon]

My expectation is still

Best case:
2020 Q4: 2 Ghz Flagship with about 2x Radeon 5700 XT performance @ near 300W TBP (80 CUs 512 bit memory-bus, GDDR6).
2021 Q1: 2.1 - 2.25 Ghz Water cooled version with ~5-10% perfomance uplift @ 350-375W TBP (80 CUs, possibly HBM2E - based on the Pro version)

Worst case:
What Coretex rumored (barely faster than 2080 Ti)

I'd rather be surprised with AMD over-delivering (with the aforementioned godly N23) than be dissapointed yet again.

 

[AtenRa]

My expectation is still

Best case:
2020 Q4: 2 Ghz Flagship with about 2x Radeon 5700 XT performance @ near 300W TBP (80 CUs 512 bit memory-bus, GDDR6).
2021 Q1: 2.1 - 2.25 Ghz Water cooled version with ~5-10% perfomance uplift @ 350-375W TBP (80 CUs, possibly HBM2E - based on the Pro version)

Worst case:
What Coretex rumored (barely faster than 2080 Ti)

I'd rather be surprised with AMD over-delivering (with the aforementioned godly N23) than be dissapointed yet again.

512bit and GDDR-6 will increase die size and power consumption.
I dont believe the flagship Navi 2.0 to come with GDDR-6 but with HBM

 

[Krteq]

...I dont believe the flagship Navi 2.0 to come with GDDR-6 but with HBM

Yep, even Linux AMDGPU kernel driver commits for Sienna (Navi21) are referring to HBM2 controller with no signs of code for GDDR6(X) controller

 

[Gideon]

512bit and GDDR-6 will increase die size and power consumption.
I dont believe the flagship Navi 2.0 to come with GDDR-6 but with HBM

Linux driver leaks seem to indicate that there are N21 parts with both GDDR6 and HBM2 on the same die (it seems really strange so this could just be obfuscation on AMDs part)

I agree thst HBM2E would be the better choice. It would generate heat-density concerns though pushing AMD more towards water cooling.

Then again it wouldn't be that much worse than Radeon VII (which is passable on air). After all it should suffice to have 2 stacks of HBM2E rather than 4 that is a case on VII. In fact it would be very challenging to fit 4 on an interposer with a 505 mm2 die.

 

[Gideon]

Yep, even Linux AMDGPU kernel driver commits for Sienna (Navi21) are referring to HBM2 controller with no signs of code for GDDR6(X) controller

Yes, seems to be the case and with 2 stacks as seemed likely. I was obviously wrong then (but could've sworn i saw an article also mentioning GDDR6 somewhere).

That should result in significantly lower power consumption for both the memory chips and the memory controller,compared to similar GDDR6 setup.

 

[Glo.]

N22 performance makes little sense according to this. An N23 based card, with 40CUs, is pretty close to 2080ti performance or a bit below depending on the resolution if it’s 2080S+10%. N22, with a rumored 60CUs, is only 10-20% above that?

You’re overestimating N23, IMO. It won’t reach that performance with just 40CUs, absolutely not with a 150W TBP.

I do agree with this. Thats just what I have been told.

The numbers/performance targets can still be very conservative.

 

[NostaSeronx]

Just a refresh on the CDNA side to keep the CDNA sub-topic up:
GFX908 = MI100 (Single die on package)
GFX909 = MI200 (Multiple die on package)
GFX91x = MI300 (X3D GPU)

On consoles:
PS5 = GFX1000/1001
Xbox Series X = GFX1020
Xbox Series S = GFX1040

 

[kurosaki]

The thing I feel is most important this round is that AMD is finally going to be a valid (real) option for 1440p with RT.
It's going to be "good enough" for the majority of people if priced right. This can be a huge selling point leading to large shifts in market share, if they can keep up with demand...

Due to how cards back in the days improved fast every year, I never have gone with a fresh top model card, I have always waited a year to see the price go down a bit, or bought the tier below. I have never paid more than $300-400 for a GPU and i'm not very keen on starting now.

 

[blckgrffn]

The thing I feel is most important this round is that AMD is finally going to be a valid (real) option for 1440p with RT.
It's going to be "good enough" for the majority of people if priced right. This can be a huge selling point leading to large shifts in market share, if they can keep up with demand...

Due to how cards back in the days improved fast every year, I never have gone with a fresh top model card, I have always waited a year to see the price go down a bit, or bought the tier below. I have never paid more than $300-400 for a GPU and i'm not very keen on starting now.

I am here with you. If I can get 2080S-ti level performance for ~$400 *with* usable RT performance @ 1440p that would be great IMO.

Given that a whole console is likely to cost between $500 and $600 with a similar performance profile, I can at least dream.

 

[TESKATLIPOKA]

Navi 23 - RTX 2080 Super performance levels +10%, @150W TBP.
...
Those were performance targets for RDNA2, that I got hint few weeks ago.

Dude. How come?

AMD promised 50% perf/watt uplift over RDNA1. Navi 23, 40 CU GPU, with 256 bit memory bus, and performance 10% above RTX 2080 Super IS JUST, EXACTLY THAT.

Nobody has been paying attention to their execution, lately, huh?

Performance in 4K: Link
Power consumption: Link
RX 5700 XT -> 100% (TBP: 225W; real: 219W)
RTX 2080 Super -> 127.7% (TDP: 250W; real: 243W)
Navi 23 40CU; 160TMU; 64ROPs; 256bit GDDR6; 240mm^2 -> 127.7 * 1.1 = 140.5% (150W TBP) according to your info.
The conclusion is that Navi 23 is supposedly 40.5% faster than RX 5700 XT with only 2/3 of TBP. That's actually 111% better perf/W instead of just 50% what AMD said!
Everyone can make their own conclusion from this.