AMD seems to be making some big changes with its Ray Tracing Engine on its upcoming RDNA 4 GPU architecture.
AMD's Next-Gen RDNA 4 GPUs To Feature Major Ray Tracing Engine Changes Versus RDNA 3
The latest rumor comes from @Kepler_L2 who has shared the patches for AMD's next-gen RDNA 4 GPUs and its RT (Ray Tracing) engine. It is stated that the AMD RDNA 4 GPUs which are expected to launch with the Radeon RX 8000 graphics card lineup are going to incorporate a new RT engine that should yield much better performance versus the existing engine featured on RDNA 3 chips.\
RT looks brand new 🤔
— Kepler (@Kepler_L2) April 30, 2024
RDNA3 RT was based on RDNA2 with some improvements. RDNA4 RT looks completely different.
— Kepler (@Kepler_L2) April 30, 2024
AMD has been on an uphill battle against NVIDIA who have been a generation ahead of them when it comes to ray tracing support. Although the first generation of ray tracing support came to AMD in 2020 with the debut of the RDNA 2 graphics family (Radeon RX 7000), NVIDIA introduced back in 2018 with its Turing (GeForce RTX 20) lineup.
Despite launching a year after NVIDIA, the RDNA 2 GPUs lacked in front of the Turing GPUs and had an even more difficult time competing against the Ampere (GeForce RTX 30) lineup. With the current Ada (GeForce RTX 40) GPUs, NVIDIA is still miles ahead of AMD's latest Radeon RX 7000 (RDNA 4) lineup.
Although it remains doubtful if AMD will catch up to NVIDIA's strong RT leadership in games but it looks like we can expect some big changes with its RDNA 4 GPUs. Kepler goes on to state that the RDNA 3 ray tracing engine was an upgraded version of RDNA 2 which is also going to be a similar case for Sony's PS5 console which is going to use a custom RDNA GPU with elements of the RDNA 4 GPU such as BVH8 traversal while RDNA 2 and RDNA 3 GPUs currently only support BVH4 traversal.
Based on Kepler_L2's post at Anandtech forums, the GFX12 (RDNA 4) RT block looks very different with the complete removal of BVH4 traversal. It will be interesting to see what gains come to RDNA 4 GPUs in terms of ray tracing performance. The company has already outlined the use of AI for its FSR algorithm which will bring them on par with NVIDIA's DLSS and Intel's XeSS technologies which have been using AI-accelerated deep learning models for years now.
AMD RDNA Generational GPU Lineup
| Radeon Lineup | Radeon RX 5000 | Radeon RX 6000 | Radeon RX 7000 | Radeon RX 8000 |
|---|---|---|---|---|
| GPU Architecture | RDNA 1 | RDNA 2 | RDNA 3 / RDNA 2 | RDNA 4 |
| Process Node | 7nm | 7nm | 5nm/6nm | 4nm? |
| GPU Family | Navi 1X | Navi 2X | Navi 3X | Navi 4X |
| Flagship GPU | N/A | Navi 21 (5120 SPs) | Navi 31 (6144 SPs) | Navi 41 (Cancelled?) |
| High-End GPU | Navi 10 (2560 SPs) | Navi 22 (2560 SPs) | Navi 32 (4096 SPs) | Navi 48 (4 SEs?) |
| Mid-Tier GPU | Navi 12 (2560 SPs) | Navi 23 (2048 SPs) | Navi 33 (2048 SPs) | N/A? |
| Entry-Tier GPU | Navi 14 (1536 SPs) | Navi 24 (1024 SPs) | Navi 34 (1024 SPs)? | Navi 44 (2 SEs?) |
News Sources: Videocardz, TweakTown,
