Introduction

GSC Game World's "S.T.A.L.K.E.R. 2: Heart of Chornobyl" is a brand-new entry in the legendary series enjoyed by millions of players worldwide. The game features a unique combination of first-person shooter, immersive sim and horror elements. Combined with the unprecedented scale of a 64-km² radioactive zone in a photorealistic seamless open world, advanced graphics, freedom of choice, and with the thick atmosphere of a deadly adventure, it is shaping up to be the ultimate S.T.A.L.K.E.R. experience.



Developed using a heavily modified version of Unreal Engine 5, it incorporates several cutting-edge technologies, including:

• Nanite virtualized geometry
• Lumen, an advanced lighting system for global illumination and reflections
• World Partition
• Virtual Shadow Maps
• MetaHuman
• Niagara VFX system
• Chaos Physics for realistic simulation of clothes, chains, hair, and belts

The PC version supports several advanced features from day one:

• NVIDIA's Deep Learning Anti-Aliasing (DLAA)
• NVIDIA's DLSS Super Resolution and Frame Generation (DLSS 3)
• Intel's Xe Super Sampling 1.3 (XeSS 1.3)
• AMD's FidelityFX Super Resolution 3.1 (FSR 3.1) upscaling and Frame Generation

The game also supports UE5's Temporal Super Resolution (TSR), but the standard quality levels like "Quality," "Balanced," or "Performance" do not work in this game. Instead, players need to adjust the render scaling ratio in the game settings, which ranges from 25% to 100% across all resolutions. In our tests, we used the following TSR render scales:

• Quality mode at 70%
• Balanced mode at 60%
• Performance mode at 50%

To run S.T.A.L.K.E.R. 2: Heart of Chornobyl at maximum graphics settings and reasonable framerates at native resolution, a powerful GPU is necessary. Therefore, upscaling solutions are crucial. Different games have varying implementations of NVIDIA's DLSS, Intel's XeSS, AMD's FSR, and UE5's TSR. We are excited to examine how these temporal upscalers perform in S.T.A.L.K.E.R. 2: Heart of Chornobyl.

Below, you'll find comparison screenshots at 4K, 1440p, and 1080p resolutions, showcasing different quality modes for TSR, XeSS, FSR, and DLSS. Screenshots for TAA, DLAA, Native FSR 3.1 and XeSS, and DLSS/FSR 3.1 Frame Generation are also available in the dropdown menu. For a dynamic view of these technologies in motion, watch our side-by-side comparison video. This video reveals issues such as shimmering or temporal instability that might not be evident in still images.

All tests were conducted using a GeForce RTX 4080 GPU at Epic graphics settings. We also used a GeForce RTX 3080 and Radeon RX 7900 XT for additional testing. The game features DLSS Super Resolution and DLSS Frame Generation version 3.7.0.

Screenshots

Side-by-Side Comparison Video

Conclusion

Similarly to other Unreal Engine 5 titles, "Stalker 2: Heart of Chornobyl" relies heavily on upscaling technologies, which are enabled by default when you first launch the game, even Frame Generation is enabled by default, too. This makes sense, as the game can produce very impressive—yet demanding—visuals with Unreal Engine 5, especially at 4K resolution. Without upscaling the game runs at relatively low FPS, even on high-end hardware. There is one important note that we would like to point out right off the bat: player shadows are very jittery in motion, particularly when the shadows are interlacing with the grass. This is a general issue in this game, and it's not caused by upscaling solutions as it is visible at native TAA, FSR, XeSS and DLAA. Also, the native TAA implementation in this game is extremely poor, producing a very shimmery image with extreme ghosting and smearing artifacts around player weapons across all resolutions.

Upscaling Quality
With upscaling being essentially a requirement in this game, it is very important to deliver a stable image across different upscaling solutions, however, depending on the selected resolution, we would say the results are a bit mixed:

• The FSR 3.1 upscaling implementation is extremely underwhelming in this game. At 4K resolution in its "Quality" mode, the small details in tree leaves, vegetation and of thin steel objects are noticeably degraded, the overall image looks very blurry, even when standing still, and this is clearly visible in our screenshots compared to other upscaling solutions, where even the TSR image looks a lot better, pretty unusual. The FSR 3.1 image is also suffering from disocclusion artifacts and ghosting, mainly around player weapons in motion, especially when interlacing with the grass. The shimmering in vegetation in motion is an issue as well, especially on the grass, and the visibility of these artifacts is more apparent at 1440p resolution. Speaking of 1080p resolution, the FSR 3.1 image is completely broken, producing simply a wrong image quality with extreme loss of all details, it looks like an oil painting. If we compare it to the TSR image, the difference in image quality is huge, which indicates that something is definitely wrong with the FSR 3.1 implementation in this game. After further investigation, we found out that FSR 3.1 does not work correctly if the internal resolution is 720p and below, which means that 1080p FSR 3.1 "Quality" and 1440p FSR 3.1 "Performance" mode will be affected by this issue.
• The DLSS Super Resolution implementation is excellent at 4K resolution, producing a very crisp, detailed and stable image in motion, without shimmering in vegetation or ghosting issues. Compared to native TAA solution, it's a night and day difference across all resolutions in terms of overall image quality and stability. Things are a bit different at 1440p and 1080p resolutions as the DLSS image tends to have small breakups in motion, specifically on the edges of tree leaves, however, the shimmering in vegetation is not an issue in the DLSS image, even at 1080p resolution. With DLAA enabled, the overall image quality improvement is even higher, offering the best graphical experience overall when compared to the native TAA solution, FSR 3.1, DLSS or XeSS.
• The XeSS 1.3 implementation in its DP4a mode exhibits similar amount of pixelation and shimmering on the grass, tree leaves and vegetation in general as the FSR 3.1 image at 1440p and 1080p. The XeSS 1.3 image also has slightly visible disocclusion artifacts around player's weapons when interlacing with the grass in particular, however, the image is completely free of ghosting with XeSS 1.3 enabled. The image quality is different at 1080p resolution as XeSS 1.3 as its DP4a mode is struggling to retain details in vegetation, producing the image with visible empty pixels instead of reconstructing details in tree leaves.
• The TSR implementation is stable in terms of pixelation and shimmering in vegetation across all resolutions, the ghosting artifacts around player's weapons are still there, however, the visibility of these artifacts is very minimal. The TSR image quality at 1080p resolution is rendered correctly with the right amount of detail in vegetation, and it's not broken with an internal resolution of 720p or below. Actually, in this game the TSR image is the second best, after DLAA/DLSS, in terms of image details and stability compared to other upscaling solutions, which is quite unusual and somewhat impressive.

Frame Generation
In S.T.A.L.K.E.R. 2: Heart of Chornobyl, both Frame Generation solutions have a few issues in common:

• DLSS Frame Generation in this game does not work during in-game cutscenes or when browsing your PDA, but works just fine when looking into your inventory. Also, running DLSS Frame Generation on an 8 GB GPU, the RTX 4060 for example, might be a problem: as it is constantly loading and unloading generated frames into the VRAM every time you look at your PDA, which might cause performance issues, even at 1080p, in prolonged gaming sessions depending on your in-game location. Remember the jittery shadows that we pointed out in the beginning of our conclusion? With DLSS Frame Generation enabled, this issue is amplified, and it is more visible across all resolutions and output framerates. On a positive note, the DLSS Frame Generation implementation does not have any jittering issues on the in-game on-screen UI, and it is running very well in terms of overall smoothness.
• FSR 3.1 Frame Generation exhibits the same issues: it also does not work during in-game cutscenes or when browsing your PDA, it might have performance issues on 8 GB GPUs as well because it is constantly loading and unloading generated frames into the VRAM every time you look at your PDA, and the jittery shadows are even more distracting with FSR 3.1 Frame Generation compared to DLSS Frame Generation, but the in-game UI is stable, same as in the DLSS Frame Generation image. Also, FSR 3.1 Frame Generation does not engage sometimes after you enable it from the menu, and it requires restarting the game completely to be applied correctly—DLSS Frame Generation does not have this issue. To alleviate any concerns over the GPU hardware used, we tested FSR 3.1 upscaling and Frame Generation using not only a GeForce RTX 4080 GPU, but also a GeForce RTX 3080 and Radeon RX 7900 XT, to see how FSR 3.1 upscaling and Frame Generation would perform on different GPU architectures—the results were identical.

Performance
Regarding overall performance, the DLSS, TSR, XeSS 1.3 and FSR 3.1 implementations in "S.T.A.L.K.E.R. 2: Heart of Chornobyl" offer lower performance gains compared to the norm set by previously tested games that use the same technologies. Usually, going from native rendering to an upscaler set to "Quality" mode will grant a solid 45% performance boost, or even higher in some games, but in S.T.A.L.K.E.R. 2, the upscaling performance increase is only around 30% in "Quality" mode compared to native rendering at 4K resolution, and around 20% at 1440p and 1080p resolutions. With DLSS Super Resolution, TSR, XeSS 1.3 or FSR 3.1 in "Quality" mode and DLSS/FSR Frame Generation enabled, you can expect doubled FPS across all resolutions when compared to native rendering. The native FSR and XeSS modes have a performance cost of around 6% compared to the native TAA solution, and DLAA offers the best graphical experience overall while running at basically the same framerate as the native TAA solution. What's more, DLAA can also be combined with DLSS 3 or FSR 3.1 Frame Generation for both better than native image quality and FPS.