New Joint AMD-Samsung Radeon GPU: Ray Tracing, Variable Rate Shading

At Computex this week, AMD announced that its upcoming Radeon GPU built in collaboration with Samsung will offer capabilities like ray tracing and variable rate shading. These features point in opposite directions, as far as adding new capabilities to graphics hardware.

Variable rate shading, also called coarse pixel shading, reduces the workload on the GPU. Microsoft actually defines this as a reverse form of MSAA (Multi-Sample Anti-Aliasing), which is rather entertaining. Variable rate shading allows data from the same pixel to be spread over multiple pixels, reducing the overall GPU workload. Nvidia has some examples of how this can be deployed:

Ordinarily, every pixel would be shaded like the blue (1×1) test case. With variable rate shading, data from individual pixels can be used across larger areas. This reduces the overall GPU workload. Qualcomm has added VRS support, but AMD would be the second mobile GPU vendor to announce the feature.

The other major feature coming along for the ride is ray tracing. The unnamed GPU will be the first ray tracing capable mobile GPU to actually ship in a system. Imagination Technologies announced a ray tracing chip years ago, but to the best of our knowledge that solution, the GR6500, has never shipped in a consumer device.

We don’t know exactly what GPU technology AMD has baked into this chip, but the product is intended for 2022 flagships, making it likely that we’ll see some RDNA3 advances baked in.

The AMD-Samsung partnership has always been an interesting one, and we’re curious to see what kind of products come out of it. AMD originally owned the Imageon graphics core that Qualcomm bought and spun into Adreno, but it’s been years since the company built a mobile solution.

We’re especially curious to see if any of the IP from this effort shows up in AMD’s own low-power products at a later date. AMD’s deal with Samsung explicitly licensed this technology for smartphones and tablets, not other device categories. Based on what we know publicly about the deal, AMD seems to have reserved the right to use this new, low-power core in certain products of its own. We don’t have any idea which products those might be, or where the hardware might tip up, but AMD and Intel are currently facing encroachment from ARM-based chips across multiple business segments. A new low-power graphics core can scarcely be a bad thing.