PC gamers now have a breadth of choice regarding upscaling solutions, thanks to NVIDIA DLSS (recently updated to version 3.0, which includes the unique Frame Generation component), AMD FSR (updated to version 2.1 last month), and the recently launched Intel XeSS.
A new direct comparison between all three upscaling technologies has been released by Tellusim Technologies, maker of the Tellusim Engine (and the GravityMark GPU benchmark). Tellusim might not be a familiar name to most readers, but its creator is none other than Alexander Zapryagaev, who previously co-founded the more famous Unigine Corp. (whose engine powered the newly released MMO Dual Universe, available on Steam).
Zapryagaev tried some extreme upscaling ratios, finding that while DLSS showed the best quality, FSR turned out to be the most stable. XeSS is definitely behind the two in both regards.
An extreme upscaling ratio of 1:36 can make Full HD (1920×1200) resolution from 13h DOS mode (320×200). Let’s see how low we can go without high image degradation. We will start from 200 % (1:4) and go to an extreme 600 % (1:36).
The first test is the checkerboard test with simple animated objects. Nvidia DLSS shows the best quality but starts shaking after 400%. AMD FSR2 is stable in all modes. We will omit any conclusions of Intel XeSS quality because it’s running on Nvidia GPU.
The second test is just a lower camera position with the checkerboard going to the horizon. Same results here.
Let’s take a look at a game-like scenario with dynamic lighting and animation, relatively low color contrast, and a lot of blue noise. All the upscaling libraries have the same input data with blue noise and volumetric lighting. The target rendering resolution is 2K. The source image size for 600% mode is only 428×241, but the upscaler turns it to the target resolution.
Overall, AMD FSR2 is the most stable at all resolutions, with even better denoising than DLSS 2.4. The results from DLSS 3.0 and XeSS running on Intel GPU will be added later.
It's worth noting that this is more of an experiment than a real use-case scenario. The standard implementation of FSR only allows 2x upscaling with the Performance Mode, while DLSS goes up to 3x if you select Ultra Performance (though that's really only recommended when playing at 8K resolution), and XeSS has an upscaling factor of 2.3x with the Ultra Performance mode.
As such, finding out which upscaling technology is most stable at 400% or beyond is only interesting on an academic level.