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If the RX 6900 XT was priced at £650 / £700, Nvidia would be beaten

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I'm not sure, wouldn't they need a new / redesigned GPU die, I thought Navi 21 maxed out at 80 CUs?

But, I think a super overclocked RX 6900 XT could sell reasonably well if it managed to overtake the RTX 3090 in 90% of games, with RT off, if priced a bit lower. Overclocking the RX 6900 XT will get a bit more 'milage' because of the extra shader units (in terms of TFlops). Maybe upto 2600mhz will be possible on air.

To overtake the RTX 3080 TFlop count, it would need a massive overclock of 2900mhz! Probably only remotely possible when LN2 cooled.
Just compare the specs of the RTX 3080 and RTX 2080 TI. The RTX 3080 has around 24% better performance, and has 2x the shader units and over 2x the TFlop count (which increased clock rate boosts further).

That accounts for most of that boost, but the RTX 3080 also has 8 extra ROPs and a bit higher memory bandwidth, which I imagine helps a bit with 4K performance .

2x TFlops won't double the performance of a GPU as you pointed out. But, that doesn't mean AMD has the luxury of ignoring this factor (AMD didn't with RDNA 2, they more than doubled in from the RX 5700 XT to the 6800 XT). TFlop count matters more when combined with other factors.

So basically you are telling me your original point was flawed as there are other factors that count when determining the performance of a GPU.
 
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My suspicion is that the reason the 6800XT and 3080 trade blows at 1080p and 1440p, but then the 3080 takes the crown at 4k is because the 6800XT is memory bandwidth constrained at 4k. This is just speculation on my part but I kinda suspect the frame buffer for 4k is just too much for Infinity Cache to handle. The problem that the 6900XT has is that it has the exact same memory bandwidth that the 6800XT has, and from what I've been told the size of the Infinity Cache is the same as well. So if the 6800XTs GPU is memory bandwidth starved at 4k then we can expect the same for the 6900XT I'd be willing to bet that the actual % gains of the 6900XT over the 6800XT specifically at 4k are quite small.

6800XT is not memory bandwidth bound.

https://www.computerbase.de/2020-11..._4k_limitiert_er_in_hohen_aufloesungen_update

This shows that a 7.5% memory overclock only got a 1% performance uplift at 4k.

I think what you will find is that Ampere just has a smaller performance drop off vs Turing, RDNA, RDNA2 as you increase resolution due to the number of shaders. You saw similar with Radeon 7 vs 5700XT where at 1080p the 5700XT would often be ahead, at 1440p they would be neck and neck and at 4k the Radeon 7 would be faster. If you go back further it was the same with Fury X vs 980Ti. 980Ti was faster at 1080p and 1440p but at 4k it was a much closer battle.


As far as RT is concerned we have some AMD sponsored games where AMD is ahead in RT performance like Dirt 5 and WoW Shadowlands and NV sponsored games or early adopter RT games where NV is ahead. I think we need to wait for neutral implementations where devs have worked with both AMD and NV to get the best out of the RT hardware available to see who is going to come out ahead. I suspect it will be NV but I don't think it will be as bad as some benchmarks are showing.
 
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As far as RT is concerned we have some AMD sponsored games where AMD is ahead in RT performance like Dirt 5 and WoW Shadowlands and NV sponsored games or early adopter RT games where NV is ahead. I think we need to wait for neutral implementations where devs have worked with both AMD and NV to get the best out of the RT hardware available to see who is going to come out ahead. I suspect it will be NV but I don't think it will be as bad as some benchmarks are showing.

People need to start posting RT results in the benchmark threads here. I suspect AMD have optimised RT shadows to the point that they are only edge traced and filled with more traditional methods. This would explain why in more complex situations where other dynamic events could alter shadows that they do so badly.
 
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People need to start posting RT results in the benchmark threads here. I suspect AMD have optimised RT shadows to the point that they are only edge traced and filled with more traditional methods. This would explain why in more complex situations where other dynamic events could alter shadows that they do so badly.

I think it is just too early to tell yet with not enough indepth investigation to really draw any meaningful conclusions beyond 'it seems a bit screwy'.
 
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No they would not as lots of people only buy nvidia, as the market leader, regardless of price.

Selling a 6900 XT for 650 is silly, considering the demand, it would be insane.
 
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6800XT is not memory bandwidth bound.

https://www.computerbase.de/2020-11..._4k_limitiert_er_in_hohen_aufloesungen_update

This shows that a 7.5% memory overclock only got a 1% performance uplift at 4k.

I think what you will find is that Ampere just has a smaller performance drop off vs Turing, RDNA, RDNA2 as you increase resolution due to the number of shaders. You saw similar with Radeon 7 vs 5700XT where at 1080p the 5700XT would often be ahead, at 1440p they would be neck and neck and at 4k the Radeon 7 would be faster. If you go back further it was the same with Fury X vs 980Ti. 980Ti was faster at 1080p and 1440p but at 4k it was a much closer battle.


As far as RT is concerned we have some AMD sponsored games where AMD is ahead in RT performance like Dirt 5 and WoW Shadowlands and NV sponsored games or early adopter RT games where NV is ahead. I think we need to wait for neutral implementations where devs have worked with both AMD and NV to get the best out of the RT hardware available to see who is going to come out ahead. I suspect it will be NV but I don't think it will be as bad as some benchmarks are showing.

The problem is I've seen benchmarks in other games which show quite a large possible swing at 4k and my gut feeling on this is that Infinity Cache as a method for reducing memory bandwidth usage is something that could be very hit or miss, or at least dependent on driver profiles. I don't know enough detail about that, but I do know that the frequency with which some values in memory are used is very frequent and some others no where near as much and so what you store in the Infinity Cache matters a lot, and I'd be interested to know how they're doing that and if game specific optimizations are necessary. That could be a deal breaker at certain resolutions in certain games. It is just speculation on my part though and I was up front about that, but something doesn't feel quite right if you look at a wider range of games at 4k Ultra.

Time will tell, we need more next gen games from the consoles, we need more ray traced games.
 
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The problem is I've seen benchmarks in other games which show quite a large possible swing at 4k and my gut feeling on this is that Infinity Cache as a method for reducing memory bandwidth usage is something that could be very hit or miss, or at least dependent on driver profiles. I don't know enough detail about that, but I do know that the frequency with which some values in memory are used is very frequent and some others no where near as much and so what you store in the Infinity Cache matters a lot, and I'd be interested to know how they're doing that and if game specific optimizations are necessary. That could be a deal breaker at certain resolutions in certain games. It is just speculation on my part though and I was up front about that, but something doesn't feel quite right if you look at a wider range of games at 4k Ultra.

Time will tell, we need more next gen games from the consoles, we need more ray traced games.

You are better off tracking performance relative to the 2080Ti. As resolution goes up the 6800XT pulls away from the 2080Ti. The 3080/3090 just pull away even more due to having so much shader performance.
 
Soldato
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RT is a RTX 3090 feature only (if playing at 4k resolution), due to the performance hit - It can look nice / realistic, but so can rasterized effects. Just give them 4-5 years, it will be the mainstream and won't perform like crap.

AMD needs to concentrate first on improving general graphics performance, particularly at 4K. They aren't quite there yet, I do think RDNA 3 is gonna be another large performance leap for AMD though, especially with no clear plan from NV, regarding the next gen / 5nm GPUs so far. As RT hardware is built into each Compute Unit, adding more CUs would boost the TFlop count and ray tracing performance. You can also assume an increase in TMUs too, as this tends to be tried to the Compute Unit count, so there would be an increase in texture rate too.
 
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Soldato
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Soo... If the RX 6900 XT isn't bound by memory bandwidth (much), that pretty much leaves the raw processing power / TFlop count of the GPU. This GPU already has higher theoretical performance in other areas (likely similar memory bandwidth), vs the RTX 3090, and had a doubling of ROPs (128), since the RX 5000 series.

Feel free to come up with an alternative theory, even if the temptation is simply to say "you're wrong" :D

Some overclocked editions of the RTX 3090 can hit 40 TFlops or higher, that's about a 73% increase vs the stock RX 6900 XT, but I think AMD will catch up.
 
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Soldato
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couldn't someone just underclock the 6800 XT / 6900 memory a lot (say 50%)? That would give a clearer indication of how much difference memory bandwidth makes.
 
Soldato
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Igor from Igor's Lab reckons the overclocked RX 6800 XT "wins against the GeForce RTX 3080 FE in almost all gaming benchmarks". He clocked it at around 2500 Mhz, using some power modding software.

Can anyone verify if this is true or not? Can a RX 6800 XT clocked at around 2500mhz consistently beat a stock RTX 3080? Clearly, he wasn't talking about Ray tracing games.

Link here:
https://www.igorslab.de/en/amds-rad...-thanks-morepowertool-andboardpartner-bios/2/

If it's true, I'm sure factory overclocked RX 6800 XTs will sell well, if priced reasonably.
 
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Soldato
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I suppose no one is bothered about the factory overclocked modes, when the reference models are still so difficult to buy...
 
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