Potential issues with ray-tracing performance in Unreal Engine 4 on RDNA 4 graphics cards might not be exclusive to AMD.
A troubling issue has been discovered in the Nvidia-specific version of Unreal Engine 4, affecting the performance of games like The Ascent and Hellblade: Senua's Sacrifice on AMD RX 9000 series and Intel Arc B580 graphics cards when ray tracing is enabled.
The root of the problem lies in the engine's proprietary ray-tracing technologies, which are tailored for Nvidia's RTX GPUs. This custom code results in poor performance and stuttering on competing GPUs due to less efficient support or a lack of tailored drivers for these proprietary Nvidia-specific ray-tracing features.
In The Ascent, the RX 9070 struggled with substantial stuttering, managing an average of over 60 FPS but yielding 0 FPS 1% and 0 FPS 0.1% lows. The RTX 5070, on the other hand, experienced artefacting issues causing black bars at the top of the screen. Similarly, in Hellblade: Senua's Sacrifice, the RX 9070 performed at around 45 FPS average but suffered from 0 FPS 1% and 0.1% lows, while the Arc B580 managed the same 45 FPS average but suffered from terrible 8 FPS 1% and 0.1% lows, causing large stutters.
The stuttering is not exclusive to AMD and Intel GPUs, as Nvidia's own RTX 5070 also experienced issues in The Ascent. Further testing is needed to determine if the stuttering issues in the vanilla version of Unreal Engine 4 exist on the Intel Arc GPUs.
This situation has led to criticism that Nvidia’s customizations effectively restrict smooth ray-tracing experiences to their own hardware and create problems for other GPU manufacturers in these Unreal Engine 4-based titles.
Tech Yes City published a deep dive on the severe stuttering issues in Unreal Engine 4 games with ray-tracing on AMD’s RX 9000 series GPUs, also found on Intel’s Arc B580. The tests included The Ascent and Hellblade: Senua's Sacrifice, not to be confused with Hellblade 2.
It is worth noting that both The Ascent and Hellblade: Senua's Sacrifice run on an Nvidia RTX branch of Unreal Engine 4, featuring Nvidia-specific ray-tracing technologies designed specifically for Nvidia GPUs. Other Unreal Engine 4 games based on the vanilla build of the engine were not tested to see if the stuttering issues existed on the Intel Arc GPUs.
As the Arc B580 is a significantly weaker GPU, in a much lower price class compared to the RX 9070, it is possible that the performance drop-offs observed in The Ascent and Hellblade: Senua's Sacrifice on AMD and Intel GPUs may be due to the Nvidia-specific version of Unreal Engine 4, rather than potential driver issues on AMD's side.
Performance dropped off a cliff when ray tracing was turned on in Hellblade: Senua's Sacrifice on the RTX 5070 and RX 9070, possibly the only reason the Arc B580 was able to pump out average frame rates similar to those of the RX 9070. Turning on DLSS rectified the artefacting issues on the RTX 5070 in The Ascent.
In conclusion, the stuttering issues in The Ascent and Hellblade: Senua's Sacrifice on AMD and Intel GPUs may be due to the Nvidia-specific version of Unreal Engine 4, rather than potential driver issues on AMD's side. Further testing is required to fully understand the extent of this issue and to determine if it affects other games based on the Nvidia-specific version of Unreal Engine 4.
Technology's proprietary ray-tracing features in Unreal Engine 4, tailored for Nvidia's GPUs, have sparked debate about artificial-intelligence driven decisions creating compatibility issues with gadgets from rival manufacturers. This discrepancy between Nvidia-specific and other GPUs is exemplified in the performance of games like The Ascent and Hellblade: Senua's Sacrifice on AMD RX 9000 series and Intel Arc B580 graphics cards.
