A mystery APU has been spotted in the latest Linux Coreboot patch from AMD which supports ray-tracing in a first. The unidentified APU with the GPU ID: gfx1013 in LLVM is based on the 1st Gen RDNA architecture (Navi 10), but can process RDNA 2 instructions (GFX 10.3), including those for ray-tracing such as:
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What’s certain is that the device is an APU with support for RDNA 2 and ray-tracing instructions (as stated by the author). What’s not certain is which APU family does it belong to and why it’s being grouped with the lower-end (RDNA 1) Radeon RX 5000 series GPUs. (Update: It’s Navi 10 based), thanks to Coelacanth).
Although the APUs powering the PS5 and Xbox Series X|S consoles also support ray-tracing, but they’re based on the newer RDNA 2 design and are a special semi-custom design. It’s possible that we’re looking at the upcoming Rembrandt APUs which are going to leverage 6nm Zen 3+ cores along with an integrated RDNA 2 graphics. It’s possible that the GPU featured on these APUs is a hybrid between RDNA 1 and 2 which wouldn’t be surprising as they won’t support all the features of the discrete Navi 2x lineup.
