AMD gets serious: When the volcano flares up again with RADV and 14% more ray tracing performance on RDNA 4,

Yes, they still exist – the good news for Linux gamers with AMD graphics cards. While Windows users continue to fight their way through the driver jungle of adrenaline madness, some real heavyweights of the open source scene are working in the background on an update that is not just cosmetic, but brings tangible technology: The new RADV patch series for the Mesa graphics stack brings ray tracing under Linux on RDNA 3 and RDNA 4 GPUs in a form that is worth seeing.

A patch, not a band-aid

What landed in Mesa 25.2 shortly before the code freeze is not a small fix on the side, but a radical rewrite of the ray tracing pipeline for GFX11 (RDNA 3) and GFX12 (RDNA 4). In plain language: new shader instructions, more efficient BVH stack handling, less memory overhead. If you want to know exactly: ds_bvh_stack_rtn for RDNA 3, ds_bvh_stack_push8_pop1_rtn for RDNA 4. Sounds cryptic, but it’s basically what NVIDIA has been doing for years – only now AMD is doing it too. The driving force behind it: Natalie Vock, who as a Valve contractor is now something of a Vulkan whisperer. And what she delivers is not academic gimmickry, but tangible performance gains.

Facts, not fantasy: 14% for Quake II RTX

Quake II RTX – yes, the game that is now used as a ray tracing benchmark more often than it has ever been played – is once again the guinea pig. With the new RADV patches, an RX 9000 (specifically: RX 9070) brings a slim 14% more frames to the screen according to internal tests – mind you, with ray tracing enabled. That doesn’t sound like much? Not if you know how sensitively RTX render paths react to memory latencies and traversal logic. This 14% comes from a simple but efficient optimization: fewer stack operations, smarter use of shader ALUs, smarter instruction planning. In other words: less ballast, more output.

The true subtext: AMD is upgrading

What some people dismiss as a nerdy open source update is actually a strategic move. AMD is bringing its GPUs up to speed with NVIDIA, at least under Linux. This is not only a respectable success for Mesa, but also a silent admission: the hardware has always been able to do it – it was just never fed properly. RDNA 4, previously described more as a still life with an unclear focus, is now suddenly taking shape. And it is striking how precisely these patches are tailored to the new features, especially for 8th generation BVH traversals. This is no coincidence, but part of a long-term pipeline strategy.

What does this mean?

• For Linux gamers: Finally RTX that doesn’t feel like slideshow rendering.
• For AMD: A declaration of intent – “We can do this too, just without the G-Sync control.”
• For NVIDIA: A quiet warning shot that shows that AMD is no longer treating the software side like a stepmother.
• For Windows users? Well, it may or may not come in the Adrenalin update at some point.

Vulkan is on fire again

14% more ray tracing FPS is not a revolution, but it is a clear signal. The Vulkan driver RADV is coming of age, and AMD is finally taking the consequences of years of ray tracing at a snail’s pace. The days of being fobbed off with half-baked implementations and PR bullshit seem to be over (under Linux!). The only thing missing now is the final proof in real life, beyond Quake II RTX. But the first step has been taken.

Source: Phoronix