Ray tracing is typically seen as a trade-off between visuals and performance enhancing lighting realism at the cost of FPS. However, there's a second trade off that is talked about less: noise.I recently dedicated a video to discuss just this because there are games that don't use a high enough resolution for their effects, others with noticeable surface grain, heavy denoising that results in surface boiling, or games where ray tracing hurts texture quality to the extremes of causing noticeable responsiveness issues with lighting.All of these problems end up hurting what is supposed to be a technology that improves visual quality.What is Ray Reconstruction?Partly acknowledging this, Nvidia launched DLSS Ray Reconstruction back in 2023 to address many of these issues. As an AI-based denoiser for ray-traced games, it did offer some improvements in sharpening certain effects, but issues with noise and loss of detail remained in common scenarios.Nvidia has now updated Ray Reconstruction as part of its DLSS 4 technology suite. The DLSS 4 version replaces the old convolutional neural network (CNN) with a new transformer model.Essentially, this is a larger, higher-quality AI model with further tuning to improve denoising quality. Does this updated version address many of my complaints about ray tracing noise? Well, it's time to find out.The good news about DLSS 4 Ray Reconstruction is that it's available on all Nvidia RTX GPUs, unlike Multi Frame Generation, which is exclusive to the GeForce 50 series. While the new transformer AI model is larger and more performance-taxing depending on the GPU architecture, it doesn't require any specific architectural component just Tensor cores so compatibility remains the same as DLSS 3-era Ray Reconstruction.As you'll see later, the performance hit isn't the same across every GPU generation, but at least it works all the way back to the GeForce 20 series.Like other DLSS 4 technologies, there are two ways to access DLSS 4 Ray Reconstruction. Either it's integrated into the game itself, as seen in titles like Cyberpunk 2077 and Hogwarts Legacy, or you can override a DLSS 3 Ray Reconstruction game to use the DLSS 4 version instead via Nvidia's driver override feature.Either way, a game must already support Ray Reconstruction, but this allows most Ray Reconstruction-enabled games to be instantly upgraded to the latest version. Outside of this, third-party tools like DLSS Swapper and DLSS Updater can upgrade DLSS 3 games to DLSS 4.For the image quality analysis in this article (watch the video), I'll be directly comparing DLSS 3 vs. DLSS 4 Ray Reconstruction across several examples. To do this, I've taken DLSS 4 games and manually downgraded them to DLSS 3.7.20 Ray Reconstruction the most recent version prior to DLSS 4 while keeping everything else the same. This allows us to isolate the impact of Ray Reconstruction improvements.In some games, it's possible to switch between the transformer and CNN models for Ray Reconstruction without swapping the DLLs, but this usually affects both the ray reconstruction and upscaling components at the same time.I wanted to keep the Super Resolution model at the DLSS 4 level while changing only Ray Reconstruction, which is why I used a downgrade method for comparison. The examples in this video were captured at 4K using a GeForce RTX 5090.DLSS 4 Ray Reconstruction Image QualityLet's start with the good stuff. DLSS 4 Ray Reconstruction is a significant improvement in stability. In particular, many surfaces are less prone to boiling with the new version, eliminating one of the ugly side effects of weak denoising.In Star Wars Outlaws, for example, a game prone to boiling with DLSS 3 Ray Reconstruction the new DLSS 4 version shows huge improvements in surface stability. On the left, DLSS 3 causes a completely stationary surface to bubble when it shouldn't, whereas on the right, DLSS 4 is much cleaner. It's not 100% free of this artifact but is significantly reduced. In fact, in other areas of the image, stability improves to near-perfect levels.For a better representation of image quality comparisons, check out the HUB video below:In other examples, like Cyberpunk 2077, this improvement is most noticeable in motion. There's less bubbling as denoised ray-traced effects move, giving them greater stability and consistency from frame to frame. This is especially noticeable on some globally illuminated surfaces, where DLSS 4 Ray Reconstruction brings a significant improvement.The new version is cleaner in motion and resolves a decent level of detail more quickly. In some cases, the difference in quality is night and day so much so that DLSS 3 can look like the game is running at a lower resolution. And keep in mind, this is denoising, not upscaling, which remains the same in both examples. Changes in exposure are also much less likely to cause brief boiling, indicating that the new transformer model handles lighting adjustments better.At times, this increase in stability combines with better denoising to produce higher-resolution reflections. In the Alan Wake II example, metal reflections show boiling with DLSS 3, but switching to DLSS 4 Ray Reconstruction reduces it, making the reflection appear higher resolution since edges are more defined and consistent in motion.There's also the classic fan example that Nvidia used to demonstrate DLSS 4, and we can confirm that this is a real benefit in games. As the fan spins, revealing the roof behind each blade, DLSS 4 is much more stable, reducing both boiling and ghosting.Again, this is ghosting caused by denoising, not upscaling. Rippling water surfaces also benefit from DLSS 4 Ray Reconstruction often a source of noise but the new version does a better job of smoothing these details without introducing additional issues.One of the major issues with the original Ray Reconstruction technology was its inability to resolve texture detail on surfaces that also required denoising. In these cases, Ray Reconstruction prioritized smoothing noise over preserving textures, leading to blurry, muddy surfaces. In many instances, DLSS 4 is a major improvement in this area.For example, in Cyberpunk 2077, when looking at some shiny tiles, DLSS 3 Ray Reconstruction removes much of the marbling and surface detail, whereas DLSS 4 retains texture detail. This applies to both stationary and moving scenes, and in both cases, DLSS 4 is a clear upgrade in texture quality. In fact, the motion example looks horrible and extremely blurry with DLSS 3, whereas with DLSS 4, it looks much more like a 4K image.This improvement extends to other games like Star Wars Outlaws, where the combination of reduced boiling and better texture preservation results in significantly higher-quality surfaces across the game world. In the Alan Wake II elevator door example, DLSS 3 completely hides the fact that the surface is brushed metal, but DLSS 4 Ray Reconstruction restores this detail along with other benefits.Here's another example in Cyberpunk 2077, where the roof of the car retains clearer textures in motion with DLSS 4 Ray Reconstruction compared to previous versions. Similar benefits can be seen on various surfaces throughout the game.It's impressive how much DLSS 4 Ray Reconstruction improves surface stability, resolution, and detail and how bad prior versions of denoising can look in comparison. Denoising that blurs textures and causes boiling is not a real solution effective denoising should preserve detail as well, and we're getting much closer to that with DLSS 4.The Downsides of Ray ReconstructionDLSS 4 Ray Reconstruction isn't perfect though. Some areas haven't improved much over DLSS 3 Ray Reconstruction, and in certain cases, there are actually regressions, which isn't great. For example, in the three main games we tested all of which have native DLSS 4 integrations we noticed that DLSS 4 could occasionally introduce strange surface artifacts.In Star Wars Outlaws, stationary ray-traced effects sometimes display a grid pattern. We've zoomed in for clarity, but it's also visible at a normal viewing distance on a 32-inch 4K panel. A similar issue appears in Cyberpunk 2077, though less frequently, usually in globally illuminated areas.We also noticed some cases where DLSS 4 Ray Reconstruction reduced texture quality, separate from the previous issue. About 80% of the time, texture quality is noticeably better, but in the remaining 20%, textures can become blurrier or more smoothed out. For example, in Alan Wake II, the scene below shows improved textures in one area but worse textures in a darker section.Fortunately, in most cases, this regression isn't enough to hurt overall image quality compared to DLSS 3, as the majority of the image sees improvements especially in terms of boiling and surface artifacts. However, some tweaks to the model are necessary to ensure texture quality is consistently preserved along with denoising.Ray Reconstruction also still suffers from a noticeable difference in clarity between stationary shots and motion where standing still always results in a higher-quality image than when moving.This is, of course, due to how denoising works: if there are no changes between frames, denoising can temporally accumulate and resolve a higher level of detail. But when there are changes, achieving similar detail levels becomes much harder. Still, we would have liked to see more improvements in this area.The reality is that when you stop moving, after a second or two, Ray Reconstruction appears to slowly "load in" higher-quality surfaces. It isn't actually loading anything it's just the temporal system benefiting more and more from the lack of motion during that time.But when actually gaming, this can be noticeable, especially because in some instances, as soon as you take a step or move the camera, the overall render quality decreases. Now, DLSS 4 Ray Reconstruction in motion is certainly superior to DLSS 3, but in this area, it seems to work in basically the same way.Since there's still quite a bit of temporal accumulation happening, there haven't been major improvements to the responsiveness of the denoiser. It still takes a few frames to fully respond to lighting changes, which can create a floaty feeling when moving around and looking at reflections or illumination on surfaces.The quality of each step in the accumulation and resolution process is improved, but the number of temporal samples being used for denoising seems quite similar to previous iterations. This still causes issues in games that don't use a particularly high ray count for ray tracing. So this pet peeve we have with the responsiveness of ray-traced lighting persists even with DLSS 4 Ray Reconstruction.Performance TestingAs for performance, DLSS 4 Ray Reconstruction is more taxing than DLSS 3 Ray Reconstruction. We tested four different graphics cards using the latest version compared to DLSS 3, focusing solely on the impact of Ray Reconstruction, not upscaling. For each GPU, we adjusted the settings to something realistically playable while maintaining a similar output frame rate.GeForce RTX 5090Starting with the GeForce RTX 5090, we tested at 4K with DLSS Quality enabled, typically using the highest in-game settings. This results in around 60 FPS in Alan Wake II and Cyberpunk 2077, or a higher 90 FPS in Star Wars Outlaws.Using DLSS 4 Ray Reconstruction caused a 4% hit in Alan Wake II, a 5% hit in Cyberpunk 2077, and a 7% hit in Outlaws. So, not an insignificant impact, but quite worthwhile given the image quality is generally much better.GeForce RTX 4070 SuperThe RTX 4070 Super is less powerful and uses the previous-generation Ada Lovelace architecture. To run these games at around 60 FPS, we had to drop to 1440p with DLSS Quality and slightly lower the presets as well.But despite these changes, the impact from DLSS 4 Ray Reconstruction is quite similar to the RTX 5090: a 4% hit in Alan Wake II, a 6% hit in Cyberpunk 2077, and a 6% hit in Outlaws. Based on this, it's safe to say the Tensor cores in Blackwell and Ada are good enough to run the new transformer model at an acceptable performance cost.GeForce RTX 3090The RTX 3090 is roughly equivalent to an RTX 4070 Super in ray tracing performance, so we used the exact same settings for both GPUs. The main difference here is the architecture. What was interesting to note is that the 3090 suffers from a greater hit when using DLSS 4 Ray Reconstruction: an 18% loss to FPS in both Alan Wake II and Cyberpunk 2077.Interestingly, there is no performance impact in Star Wars Outlaws, but this is because it seems like the game forces the use of the CNN model on generations prior to the 40 series. Unlike the other two games, there is no option to switch between models the game does it for you. In this instance, it chooses Transformer for the 40 and 50 series and CNN for the 30 and 20 series, hence no impact between DLSS 3 and 4 in Outlaws on the RTX 3090.The most likely explanation for the performance difference between Ampere and Ada Lovelace is the difference in Tensor core architecture, with Ada supporting a wider range of precisions that are potentially being utilized here.GeForce RTX 2080 TiAs for Turing with the RTX 2080 Ti, this GPU is really only suitable for low-quality ray tracing today. We had to dial back the settings to 1080p with DLSS Quality and the lowest quality settings. In Alan Wake II, we saw a 27% FPS reduction using DLSS 4 Ray Reconstruction vs. DLSS 3, and a 32% reduction in Cyberpunk 2077.This makes it hard to recommend the use of the newer model on older 20 series GPUs, though it's unclear how much it matters given the overall ray tracing performance of these cards.What We LearnedOverall, we were quite impressed testing DLSS 4 Ray Reconstruction certainly much more impressed than when testing Multi-Frame Generation. The new transformer model generally results in a significant increase in visual quality. There are major improvements to stability, surface boiling, texture preservation, and overall detail, which help deliver better ray-traced surfaces.Using this technology makes ray tracing feel like less of a downgrade in detail, minimizing the "visual cost" of achieving better lighting quality and accuracy. A lot of these surface and detail issues were clear problems with DLSS 3 Ray Reconstruction and other denoising methods used in today's ray-traced games. It's nice to get ray-traced lighting, but the noise can be pretty distracting in some games, giving the presentation a soupy, low-resolution look, especially in motion.DLSS 4 is a big step in the right direction toward improving how ray-traced games look, and in all the games we tested, we were much happier with the DLSS 4 output.While it is quite an impressive improvement that should be instantly noticeable in games, I wouldn't say it's "fixed" all of my ray tracing noise complaints. DLSS 4 Ray Reconstruction still has some surface boiling in worst case scenarios, there's still a noticeable difference in detail between standing still and motion, and it still struggles to be responsive and high quality when ray counts are low. There's also a few regressions compared to DLSS 3, like the occasional weird artifact and some reductions to texture quality.But for the most part, it's worth using especially on RTX 50 and RTX 40 series GPUs, where the performance impact relative to DLSS 3 seems to be around 5%. It struggles more on Ampere-based RTX 30 GPUs but could still be worth using, while on RTX 20 series cards, you can basically forget about it due to both the performance cost and the lack of ray tracing performance in modern games. It's great to see Nvidia delivering this sort of update without locking it to a specific GPU generation, allowing as many people as possible to benefit.We do have a couple of recommendations for game developers based on this testing. First, if you're developing a ray-traced game, consider integrating DLSS 4 Ray Reconstruction. There are some other good denoising solutions in games, but often they're pretty lackluster and create a bad output. The quality from DLSS 4 is great, and there are far fewer downsides compared to DLSS 3 Ray Reconstruction.Second, we recommend allowing gamers to choose the model used for upscaling and ray reconstruction separately. In Cyberpunk 2077 and Alan Wake II, you can choose between the CNN and Transformer models, but this applies to both upscaling and denoising together. Separating those options would allow for more performance fine-tuning, especially on older GPUs like Ampere, where ray reconstruction can be taxing.Nvidia also needs to keep working on this technology because there's room for improvement with more training and tweaks. The weird artifacts need fixing, and a stronger focus on responsiveness would be nice to reduce that gap in quality between standing still and motion.Shopping Shortcuts:Nvidia GeForce RTX 5080 on AmazonNvidia GeForce RTX 5090 on AmazonAMD Radeon RX 7900 XTX on AmazonNvidia GeForce RTX 4070 Super on AmazonAMD Radeon RX 7800 XT on AmazonAMD Radeon RX 7900 XT on Amazon