AMD’s new RDNA 2 architecture has been applied to desktop computers through the RX 6000 series graphics card-this is an important version, which provides complete hardware support for the DirectX 12 Ultimate feature set, including DXR API. Yes, ray tracing is now part of AMD’s high-end products, and we want to grasp how effective the Radeon technology in the RX 6800 XT is-and how it compares with the closest competitor, Radeon. RTX3080. Benchmarks show that Nvidia’s second-generation technology is faster than AMD’s debut product, but what is the full story?
To help put these parts together, XFX sent me a factory overclocking example of the RX 6800 XT, especially the Speedster Merc 31
Regarding the actual ray tracing metrics, it’s best to refer to the video here to learn how I tested the various RT effects and a complete breakdown of how to handle them well on all our competing GPU architectures, but the main purpose of this test is Isolate the various stages of the RT pipeline to understand the performance of Nvidia and AMD, and operate in the context of three key RT effects (shadows, reflections, and global illumination).
Generally, in any RT scheme, there are four steps. First, prepare the scene on the GPU, which is filled with all objects that may affect ray tracing. In the second step, the rays are launched into the scene, traversed and tested to see if they hit the object. Then comes the next step, where the result of the second step is shaded-for example, the color of the reflection or whether the pixel is in or out of the shadow. The last step is denoising. You will see that the GPU cannot emit an unlimited amount of rays to be traced-only a limited amount of rays can be traced, so the end result looks very noisy. Denoising smoothes the image and produces the final effect.
Therefore, there are many factors at play in dealing with RT performance. Of these four steps, only the second step is hardware accelerated-the actual implementation between AMD and Nvidia is different, and GeForce cards have more hardware issues. RDNA 2 calculates the ray traversal on the computing unit, which causes resource competition, while Nvidia does it in a dedicated processor inside the RT core. The first setup stage may have a lot of CPU requirements, and the shading and denoising steps may have specific preferences for certain GPU architectures. For example, Quake 2 RTX and Watch Dogs Legion use a noise reducer built by Nvidia. Although it is not designed to run poorly on AMD hardware (Nvidia will not be able to access it when encoding it), it is indeed designed Run on RTX cards as much as possible.
In any case, in the video, my goal is to comprehensively solve the entire ray tracing pipeline problem on the two architectures, covering various effects. Ray-traced shadows were tested in “Call of Duty: Black Ops Cold War” (a title sponsored by Nvidia) and “Dust 5” (supported by AMD). I checked the ray-traced reflections in Ghostrunner in Unreal Engine 4. Here I can check the effect with some adjustments. Of course, the reflections of the “Watchdog Legion” are also placed under the microscope. I chose this product because the AMD RT hardware is used in the console to produce the effect, and through modification, I can access the console and the Nvidia noise reducer at the same time. With the help of ray tracing global lighting, 4A Games’ incredible Metro Exodus was tested in depth, and I observed a more extreme example through the Quake 2 RTX of path tracing-since the final integration has been completed, the product is now available in Vulkan RT extensions are used on AMD and Nvidia RT hardware.
what is that? I think there are some interesting results here. Ray-traced shadows are generally inexpensive on resources on the RX 6800 XT and RTX 3080-RTX 3080 will see the least wins at lower settings, and then at higher settings, as the quality of ray tracing increases Improve, this situation will increase, such as “Call of Duty” black operations. For ray tracing reflections, the effect of GPU hardware is more demanding, but in many cases the visual effect is more obvious. The higher the randomness of the reflected light, the more light is emitted. Compared with the RX 6800 XT, the performance of the RTX 3080 is better, and the rendering time is nearly half in some configurations. The efficiency advantage of RTX 3080 diminishes after a certain critical point, and what I see is global illumination: RTX 3080 can provide nearly half the time in Metro Exodus, and even provide a third of the effect in Quake 2 RTX. , But since then the amount of radiation has been increased, and the advantages of RTX 3080 have been reduced.
Generally, from these tests, the simpler the ray tracing, the more similar the effect rendering time between competing architectures. There is no doubt that Nvidia cards have more powerful functions in the entire RT pipeline, and as the complexity of ray tracing increases, the performance loss of RTX 3080 does not seem to be that big, but on the smaller end, AMD has competition force. At the same time, PlayStation 5’s “Spider-Man: Miles Morales” proved that Radeon ray tracing can produce impressive results on more challenging effects-and the performance of the GPU used is significantly lower 6800 XT. With this in mind, we do need to accept that ray tracing on the PC side is still in its early stages, especially when running on AMD hardware. At present, I can only draw general conclusions from a representative representative, but the sample size is still small. So far, we have only seen the shadow of RT in AMD-sponsored games, and I am eager to see how the future cooperation with Team Red fare can develop future games based on harsh RT effects. Although ray tracing technology has been in the PC field for more than two years, the story has just begun-I can’t wait to know what will happen next.