I think Ray Tracing will be the biggest difference between XSX and PS5. 52CUs vs 36CUs that’s a big difference.
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Yes digital foundry analysis on some titles will be extremely enlightening. Although I expect several games will have parity which some sony fans will try and construct a narrative on,
War never changes…
Not to mention the headstart in API with DXR.
If it was marketing wouldn’t they not talk about the game being on PS5 at all? Why say that you can get it on PS5 and can also get a free upgrade if you bought it on PS4, but for some reason only leave out RT?
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So far 3 games are not able to confirm the configuration on PS5!
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Far Cry 6
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Above mentioned Watch Dogs
And adding to this conversation a new info
- Roller coaster tycoon
Game devs confirm 4k for XSX but refuse to give any info about PS5 version.
Does Xbox have marketing rights for this coaster game as well now?
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A dev on era hinted that’s more to it than that, he said that the major difference was that SX was more effecient to search the raytracing structures.
Unfortunately he said he was too caught up in the heat and stopped posting shortly after that, so we never got more clarification on what we meant.
But I guess it would explain why RT reflections on ps5 games were skipping objects or using lower lods
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That’s entirely possible. It is very odd, the press release seems to highlight and sell the game on all platforms, so if the effect is active on the PS5, you’d think they would have made it known.
There very well could be some logical reason for the omission. Hopefully it’s not something as silly as Sony not having a marketing friendly term for ray tracing like DirectX Raytracing. Another possibility could be both the Xbox and PC versions use DX raytracing APIs, so they are still working on whatever API sony has in their tools.
It will also be interesting to see how RTX is implemented. If they are using RTX extensively, I guess maybe there’s a chance that the PS5 doesn’t have the performance to do what they want but I’d think even then they could lower the quality and make cutbacks to get it working. Hopefully we some clarification on this soon.
Because Ms marketing never seems to prevent confirming the PS5 version exists. But it could be a Farcry 6 situation where they are just highlighting the Xbox features.
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RT On PS5 are shader based GPU accelerated meaning it drains more TF power budget. So the more you use RT the more it consumes a lot of GPU Power budget. Resolution can drop lower for example or framerate too.
Meanwhile on XSX it is a separate dedicate block with more than 13 tf only for RT meaning XSX performance can go above 25tf while RT is on.
That is in part why you will see a big gap between the two consoles on RT first
The ray tracing difference
RDNA 2 fully supports the latest DXR Tier 1.1 standard, and similar to the Turing RT core, it accelerates the creation of the so-called BVH structures required to accurately map ray traversal and intersections, tested against geometry. In short, in the same way that light ‘bounces’ in the real world, the hardware acceleration for ray tracing maps traversal and intersection of light at a rate of up to 380 billion intersections per second.
“Without hardware acceleration, this work could have been done in the shaders, but would have consumed over 13 TFLOPs alone,” says Andrew Goossen. “For the Series X, this work is offloaded onto dedicated hardware and the shader can continue to run in parallel with full performance. In other words, Series X can effectively tap the equivalent of well over 25 TFLOPs of performance while ray tracing.”
It is important to put this into context, however. While workloads can operate at the same time, calculating the BVH structure is only one component of the ray tracing procedure. The standard shaders in the GPU also need to pull their weight, so elements like the lighting calculations are still run on the standard shaders, with the DXR API adding new stages to the GPU pipeline to carry out this task efficiently. So yes, RT is typically associated with a drop in performance and that carries across to the console implementation, but with the benefits of a fixed console design, we should expect to see developers optimise more aggressively and also to innovate. The good news is that Microsoft allows low-level access to the RT acceleration hardware.
“[Series X] goes even further than the PC standard in offering more power and flexibility to developers,” reveals Goossen. “In grand console tradition, we also support direct to the metal programming including support for offline BVH construction and optimisation. With these building blocks, we expect ray tracing to be an area of incredible visuals and great innovation by developers over the course of the console’s lifetime.”
RT is handled very similarly in both consoles and not only handled by the shaders in the PS5. If that were the case, they would not be able to support RT to the point we’ve already seen in GT 7, Ratchet and Clank, and Spider-Man. Both systems have dedicated RT hardware within the CU. The main performance advantages for the Xbox will be the gap in CUs and the additional memory bandwidth. Not a difference between how the process is handled. Also the XSX does not have a separate block that equals more than 13TF, nor do you add the two figures to reach 25TF when using RT. At peak RT performance, the system would need an additional 13TF to match what the dedicated hardware is doing. Even when this dedicated hardware is being used, it will still take away from the existing 12TF in the GPU.
You can see the RT hardware as part of the CU below:
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You’re going to see more of this. You’re going to see XSX games at full 4K/60 with PS5 games with lower res to maintain that 60 or not have 60 at all. You’ll see games with RT on XSX and not on PS5.
3rd party games will look and perform definitively better next gen. And you won’t need Digital Foundry to point out the negligible differences, it will be apparent.
And that will be fine if the PS5 is the less expensive console. But if MS matches or undercuts their price…
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The headline picture is great, I wonder whose idea it was xD
Yeah it will take a bit of perf on the gpu but not so much with dedicated RT Cores that is the separate block built in for that.
No I never said PS5 wouldn’t do RT at all but not to the extent of what is possible on XSX. The PS5 can do RT but it will be limited. In fact the PS5 doesn’t work the same since it doesn’t have this separate RT cores, since it’s GPU accelerated it still can be called hardware indeed but it is shader based, not dedicated cores for it. That is the big difference.
For example look at minecraft path tracing on XSX. Can PS5 do path tracing? Let’s wait till they say if the PS5 is a full RDNA 2 Big Navi 2x full features gpu or a low end one with just power efficiency, then RT perf ballpark will be known more.
I gave the link with the quote above by Andrew Goossen the Xbox System Architect saying over 25tf while RT it is not said by me…
I know the quote came from Goossen, I’m just saying it’s marketing speak and not indicative of how real world performance will pan out. In the image I posted, you can see how they specifically say each CU can perform four texture or ray ops per clock. Meaning, you can fully utilize the GPU in standard rasterization if you’re also adding on ray tracing.
Also in the image I posted, you can see that the XSX does not have dedicated RT cores, but instead RT hardware in the CU. This matches very closely to the AMD patents for how RDNA2 handles ray tracing. Makes no sense for them to developer a different method only for Sony. Trust me, it will be the same as what’s in the XSX. Outside of the differences I listed before, we’ll probably see some minor tweaks like support for things like “programming to the metal”, even though that doesn’t mean what it used to.
I’m just saying you’re entirely wrong about the PS5 RT support being handled entirely by the shader. We wouldn’t see GT7 running at 4K60 with RT if that were the case. My 1080ti can’t run ray tracing at a locked 60fps at 720p just to put things in perspective.
I think this is accurate. The variable clocks are causing multiple problems imo not just with ray tracing. Its hard to develop for a target when it keeps moving lol
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What do you make of this then?
“I’m definitely super excited about what the new hardware could do. Having dedicated ray tracing hardware is huge.” – Colin Penty (Gears 5 dev)
Of course both MS & Sony will try to optimize to the best of each console capacity but trust me it is just a question of time before we see big differences on RT side without mentionning the rest…
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The XSX does have dedicated ray tracing hardware, it’s contained within the CU, just like the PS5. Dedicated RT hardware does not have to mean dedicated RT cores.
I also agree that there will be a gap in RT performance but that it will be due to the difference in CU count and memory bandwidth. Not one system having hardware support for RT while the other doesn’t.
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It isn’t really marketing speak so much as Goosen explaining why it’s a big deal to have dedicated hardware acceleration. I think the only different really at all here b/t PS5/XSX is the number of CU’s with RT running in parallel. EDIT: And the bandwidth differential…forgot about that!
GT7 seems to use low res RT reflections only iirc. I’d be interested to see how ML can help XSX RT performance though. Denoising using ML might be doable and can have a huge impact on performance in a positive way.
While I agree that PS5 definitely has RT hardware, not all RT is created equal.
GT7 had the reflections generated at 540p (with lower than 60fps refresh rates in the gameplay, perhaps around 15fps given the discrepancy in the reflections and what was around the car), with objects missing from the reflections and others using lower lods, and mirror like reflections that demand less rays
It didn’t seemed anything to write home about, even considering that RT is usually very demanding, for example, not even on a 2060 you would have to scale that back on current RTX games.
Regarding how heavy it is for a 1080ti, that’s because you are trying to run the same code that was tailored for RT acceleration, it’s possible to run with shader alone provided some cuts are made, that’s what crytek is doing for example (and funny enough, the cutbacks from their implementation do match what they did in GT7), and they are supposedly running that ray tracing solution even on a xbone.
Yeah it’s an easy way to say out RT hardware is equal to 13TF of pure compute performance. However to say that the system will reach an equivalent to 25TF when using ray tracing is marketing speak and as we’ve seen in this thread, a bit misleading.