This paper was introduced at the 2025 I3D Symposium and introduces a very performant path tracing solution that was tested in the original Quake game. It basically only falls short of NVIDIA's ReSTIR in scenes with many light sources. They used a RX 7900XTX for testing. This quote is from the blog.

"The demo project features path traced global illumination and single scattering effects at frame rates over 30 FPS on NVIDIA’s GeForce 20 series or AMD’s Radeon RX 6000 series without upscaling."

This is less interesting than these quotes from the paper:

"The resulting algorithm can produce smooth, temporally stable path traced images, including indirect lighting and single scattering in a few milliseconds at full HD resolution, even on previous generation hardware from AMD’s Radeon RX 6000 series or NVIDIA’s GeForce 20 series such as the AMD Radeon RX 6800 XT or the NVIDIA GeForce RTX 2080 Ti."

A few ms overhead to go from almost a pitch black sparse PT input to something fairly close to ground truth.

"In practice, we found 2 SPP for 2-bounce surface paths and 2 SPP for volume paths (7 rays in total: 1 for G-Buffer creation, 2 × 2 surface rays, 2 volume rays) an optimal compromise between performance and quality, resulting in around 60 FPS in most scenes of Arcane Dimensions. For older hardware, the surfaces can also be traced with only 1 SPP or, if a slight bias is acceptable, the path length can even be reduced to trace direct light only, and the path tail is read from the irradiance cache. Although this method is biased, it results in more than 120 FPS in most scenes, even on previous generation hardware, while achieving a similar error at low sample counts."

I know very little about ray tracing but enough to know that this research paper is a very big deal. Achieving 120FPS native 1080p (AFAIK is also the PT rendering resolution) on RDNA 2 GPU is just insane and nothing like the overhead of NVIDIA's ReSTIR algorithm. And no this is not a half baked screen space reliant and probe based ray tracing implementation as in most current gen games except a few outliers. Excitingly it's a full blown world space reliant path tracer.

Was really hoping for a ReSTIR like breakthrough in RTRT, but wasn't expecting it this soon. The best part about the RDNA 2 GPU performance is that it could even open the door to some form path tracing on the current gen consoles.

And this wasn't even the only interesting paper unveiled at I3D 2025 (find recap here). There was two papers related to crowd simulation, an efficient voxel game renderer, neural muscle calculations, a neural compression of 3D meshes, NVIDIA's STF solution for neural rendering, and AMD's LSNIF solution for bypassing ray tracing cores for ray tracing of objects (BLAS).
Stay tuned for the upcoming High Performance Graphics conference in about a month, SIGGRAPH in August, and soon to be released GDC materials on work graphs because things will only get more interesting from here.