But both GPUs should support DXR 1.0 and DXR 1.1. I find it very weird. AMD has a shadows library they've built on top of DXR 1.1 (I assume) for Godfall, and then they have to patch in Nvidia support later. Cyberpunk was supposedly DXR without any custom nvidia proprietary libraries, but it won't support AMD without a patch. Why? Only thing I can think of is the performance is so divergent in different RT workloads that they're worried about getting flamed for bad performance on one platform vs the other. So basically the solution will be one RT implementation for Nvidia and one RT implementation for AMD. I suppose we'll be able to tell if there are subtle visual differences. Or maybe they'll just look pretty much the same but operate different under the hood. Benchmarking RT will be very interesting going forward.
AMD Radeon RDNA2 Navi (RX 6500, 6600, 6700, 6800, 6900 XT)
But both GPUs should support DXR 1.0 and DXR 1.1. I find it very weird. AMD has a shadows library they've built on top of DXR 1.1 (I assume) for Godfall, and then they have to patch in Nvidia support later. Cyberpunk was supposedly DXR without any custom nvidia proprietary libraries, but it won't support AMD without a patch. Why? Only thing I can think of is the performance is so divergent in different RT workloads that they're worried about getting flamed for bad performance on one platform vs the other. So basically the solution will be one RT implementation for Nvidia and one RT implementation for AMD. I suppose we'll be able to tell if there are subtle visual differences. Or maybe they'll just look pretty much the same but operate different under the hood. Benchmarking RT will be very interesting going forward.
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Deleted member 2197
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AMD was hesitant from the start about showcasing RX 6xxx ray-tracing. Perhaps their drivers and/or acceleration mechanism has issues and just need worked on. Could also be AMD making the call regarding RT in CyberPunk.
Svensk Viking
Regular
In the case of Cyberpunk, even the PS5 and Series S/X versions will run via BC mode and get the actual next-gen patch sometime next year, so it didn't come as a shock for me that raytracing won't be supported on PC RDNA2 either out of the gate.
I think it's the right call from either AMD or CDPR, first impressions are important and there's a risk AMD performing better in newer benchmarks still wouldn't break the common conception of AMD having bad RT performance from all the previous benchmarks.
I think it's the right call from either AMD or CDPR, first impressions are important and there's a risk AMD performing better in newer benchmarks still wouldn't break the common conception of AMD having bad RT performance from all the previous benchmarks.
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Deleted member 13524
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Wait Anandtech isn't doing more GPU reviews?
Lol, poor consoles. Dont even bother with RT for those then.
I was thinking not in terms of support, but as you say, severe performance divergence. Is there a connection between inline RT and cache locality for properly leveraging rdna2's infinity cache?
I wish that we have more Synthatic Values. Since Anandtech is gone only Heise.de is doing syntethic benchmarks. You can reed this article here. As a long term subscriber i hope they will add the tables for the synthetic benchmarks. Without a table we do not have any values (this is 2 bigger than this) to discuss. This is so frustrating 
https://www.heise.de/hintergrund/Bi...-hinter-AMDs-Radeon-RX-6800-6900-4964536.html
https://www.heise.de/hintergrund/Bi...-hinter-AMDs-Radeon-RX-6800-6900-4964536.html
Frenetic Pony
Veteran
I now wonder what this means for raytracing performance as reviewed. If support is so divergent you can't even run things properly despite following spec then... well the performance implications between the two are obvious.
Either way this also bodes very, very poorly for future crossplatform support. "You have to significantly change the entire codepath for raytracing to get performant cross vendor support, or even for it to work at all" isn't a confidence booster for use of the feature. Not that I'm totally surprised, looking at the CoD guys describing just how finicky the BVH behavior was for shadows alone in Modern Warfare was a trip. I wouldn't be surprised if a very different traversal and collision detection hardware setup performed significantly differently.
Well, I can be hopeful it'll mean everyone will just ditch triangles and use SDFs.
I would expect any API, architecture, and driver idiosyncrasies to get more thoroughly unpacked if/when we see CAD renderers implement DXR, as well as general hobbyist poking and prodding with hand-rolled RT benchmarks. Right now there's only a small handful of AAA games (which are pretty sparsely using RT), not to mention that this is happening amidst a console generation transition, two GPU launches, plus the covid-related disruptions. Growing pains were inevitable here.
Ye, some seem to expect the hardware RT in the consoles to just go unused for the rest of the gen.
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Deleted member 13524
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Ok you guys almost made me believe this.
They're still doing GPU reviews!
https://www.anandtech.com/comments/...rgb-optical-mechanical-keyboard-review/730442
Ryan Smith said:
Frenetic Pony
Veteran
It's entirely possible Nvidia has been allowing out of spec behavior without throwing any warnings or etc. This would hardly be the first time for either to do this.
And considering the utter disparity between Watchdogs Legion RT performance and Miles Morales on the same console, with fantastically similar settings, min spec targets, and use of RT, it appears the spec itself, while intended to run as a shared API, gives very little idea of good performance behavior between the two archs.
Further it appears incredibly likely that AMDs non fixed traversal structure gives opportunities the spec does not, and it's also highly likely at least some of this behavior can't be replicated at all on Nvidia. To me these latter two just add up to what Cyberpunk indicates as well. That developers may need to rebuild large parts of their RT pipelines to get good performance on both. That's a big task for a very expensive feature with rather limited uses. One of the biggest limits to visual quality is already dev time; the question I'd just ask of hardware RT is, "is it worth it?"
Lol sorry my comment was tongue in cheek. Anandtech hasn’t reviewed the last 5 new GPUs but I’m sure they’ll get around to it eventually. Maybe.
CDPR didn't say anything other than CP2077 won't work on AMD cards for RT yet, and that support for AMD will come soon. RT works in other DXR titles so that means CDPR is locking to Nvidia only, not that support for RT isn't available in drivers.
With all that RT effect I assume 30? lol.
How is the 6800 binned? I assume the 6800 is just a cut down (binned) 6800/6900xt with 60 out of 80 CUs enabled
But in order to disable 20CUs (10DCUs) you'll be left with a asymmetric CU per SE configuration since 10(DCU) isn't a exact multiple of 4(SE)
I remember CUs per SE needing to be symmetrical back in GCN days, is this no longer a limitation with RDNA2?
But in order to disable 20CUs (10DCUs) you'll be left with a asymmetric CU per SE configuration since 10(DCU) isn't a exact multiple of 4(SE)
I remember CUs per SE needing to be symmetrical back in GCN days, is this no longer a limitation with RDNA2?
Indeed CPU recommendations seem off : https://www.cpubenchmark.net/compare/Intel-i7-4790-vs-AMD-Ryzen-5-3600/2226vs3481 (or they have a multi-threading problem and only care about single thread performance)
But at least GPU are similar in performance:
https://www.videocardbenchmark.net/compare/Radeon-RX-590-vs-GeForce-GTX-1060/4025vs3548
https://www.videocardbenchmark.net/compare/GeForce-RTX-2060-vs-Radeon-RX-5700-XT/4037vs4111
