Question Speculation: RDNA3 + CDNA2 Architectures Thread

Page 215 - Seeking answers? Join the AnandTech community: where nearly half-a-million members share solutions and discuss the latest tech.

uzzi38

Platinum Member
Oct 16, 2019
2,746
6,653
146

TESKATLIPOKA

Platinum Member
May 1, 2020
2,696
3,260
136
How can there be 128 ROPs then?
Where did you get 128ROPs? Ok, Anand and others say It has 128ROPs. That's weird, because 128ROPs would mean 4SE. 4SE can have only 64CU because N31 has 16CUs per SE, yet this GPU has 70CU enabled.
 
Last edited:

Timorous

Golden Member
Oct 27, 2008
1,978
3,864
136
Where did you get 128ROPs? Ok, Anand and others say It has 128ROPs. That's weird, because 128ROPs would mean 4SE. 4SE can have only 64CU because N31 has 16CUs per SE, yet this GPU has 70CU enabled.

24x4 + 32. Bit wonky but it would add up.
 

TESKATLIPOKA

Platinum Member
May 1, 2020
2,696
3,260
136
24x4 + 32. Bit wonky but it would add up.
N31 doesn't really have 192 ROPs, but only 24 Render Backend:RB+, which can process 8 32-bit pixels.

Then W7800 would have 16 RB+ and N31 has 4 RB+ per SE.
They would have to partially deactivate It in SEs, which I find unlikely considering 7900XT had them fully activated.

I think It really has 20RB+ or 160ROPs.
 

GodisanAtheist

Diamond Member
Nov 16, 2006
8,297
9,657
136
Maybe I misunderstood the part where you mentioned 60CU and 3GHz.

You are kinda overestimating RX 6800 XT or underestimating N32.:)
RX 6800XT is only 15% faster than RX 6800 despite having 20% more CU(shaders, TMUs) and also having higher clocks.TPU
N32 is exactly RX 6800 except 1/2 of Infinity cache, but with likely higher clocked memory.
It doesn't look like N32 needs to have higher clocks than 2600MHz to be on par with 6800xt in raster and be faster in RT. For this clockspeed, I don't think It needs more than 250W.

-Well here's to hoping it comes out some day so we can see it's price/perf/power in the real world.
 
  • Like
Reactions: blckgrffn

Timorous

Golden Member
Oct 27, 2008
1,978
3,864
136
Idk, man )
Has AMD ever used an asymmetric config for RB's...
I rather suggest the reported ROP count is wrong, besides amd specs on the official site doesn't mention it as well.

Entirely possible as well.
 

coercitiv

Diamond Member
Jan 24, 2014
7,355
17,424
136
I will say maybe 7950 XTX. Faster memory and better binned for a bit more moola than the 7900 XTX. I don't think anything GDDR6 faster than 20 is shipping though.
ASRock Radeon RX 7800 XT graphics card with 16GB VRAM spotted at EEC

Yet unreleased Radeon RX 7800 XT graphics card appears on Eurasian Economic Commission regulatory office.
 

Saylick

Diamond Member
Sep 10, 2012
4,035
9,454
136
ASRock Radeon RX 7800 XT graphics card with 16GB VRAM spotted at EEC

Yet unreleased Radeon RX 7800 XT graphics card appears on Eurasian Economic Commission regulatory office.
Nice. Someone on Twitter posted this:
FywKJcgX0AAAXAH.jpeg
Rumored specs seem to line up thus far.
 

jpiniero

Lifer
Oct 1, 2010
16,800
7,249
136
Will say at Newegg, the 6800 XT models closer to $500 are drying up. Still say that doing the 7800 XT is a bad idea given the 4070 bad sales.
 

Ajay

Lifer
Jan 8, 2001
16,094
8,114
136
Will say at Newegg, the 6800 XT models closer to $500 are drying up. Still say that doing the 7800 XT is a bad idea given the 4070 bad sales.
Well, if sales are drying up on the 6800XT (not being made for a while), then AMD needs something to sell in that category - even if sales are poor for now.
 
  • Like
Reactions: blckgrffn

jpiniero

Lifer
Oct 1, 2010
16,800
7,249
136
Well, if sales are drying up on the 6800XT (not being made for a while), then AMD needs something to sell in that category - even if sales are poor for now.

Ironically enough the 7900 XT is falling to $700. Microcenter in person though.

Almost have to wonder at what point will retailers refuse to stock AMD GPUs if they won't sell at the MSRP and they have to take the hit to unload the inventory.
 
  • Wow
Reactions: Ajay

Ajay

Lifer
Jan 8, 2001
16,094
8,114
136
Ironically enough the 7900 XT is falling to $700. Microcenter in person though.

Almost have to wonder at what point will retailers refuse to stock AMD GPUs if they won't sell at the MSRP and they have to take the hit to unload the inventory.
Nothing lower than $779.99 at my Microcenter ATM. If the 7900XT hit $700 for something other than a rebranded reference card, that would be a fantastic buy. Sure seems like N32 will only be used as a 7800 non-XT to give gamers a mid-range 16G card.
 

PJVol

Senior member
May 25, 2020
854
838
136
Just curious, where will they get enough salvaged N31 chips to build 7800XT inventory, that supposedly should far outsell both 7900's?
 
Last edited:

maddie

Diamond Member
Jul 18, 2010
5,156
5,543
136
Just curious, where will they get enough salvaged N31 chips for a retail 7800XT stock, that supposedly should far outsell both 7900's?
They won't. Performance deficit of RDNA 3 dictates cuts in die. Smaller margins, no loss.
 

PJVol

Senior member
May 25, 2020
854
838
136
Wouldn't that kind of franken-chip, if it exists, be better for mobile?
I don't get what makes it preferred for the mobile?
Anyways, this could only solve part of the problem - cost, while the other part - not having enough N31 downbins - is yet to be solved.
 
Last edited:

maddie

Diamond Member
Jul 18, 2010
5,156
5,543
136
I don't get what makes it preferred for the mobile?
Anyways, this could only solve part of the problem - cost, while the other part - not having enough N31 downbins - is yet to be solved.
They will have to cut functioning CU from N31 die to have a reasonably improved 7800XT vs 6800XT , if N32 can't really replace 6800XT, as appears likely. In other words that need more than 60CU at present performance levels to replace 6800XT. Bad for AMD but such is the reality.
 

jpiniero

Lifer
Oct 1, 2010
16,800
7,249
136
They will have to cut functioning CU from N31 die to have a reasonably improved 7800XT vs 6800XT , if N32 can't really replace 6800XT, as appears likely. In other words that need more than 60CU at present performance levels to replace 6800XT. Bad for AMD but such is the reality.

That's more of an argument for cancelling N32 than it is doing a further cut N31.