On RDNA 2 architecture
Samsung does use AMD architecture-based GPUs in its non-top-end Exynos SoCs. The Exynos 1480 platform has appeared on the Internet, and it has an Xclipse 530 GPU.
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The characteristics of the GPU are unknown, but it is known that it is based on the RDNA 2 architecture, while the Exynos 2400 will receive the Xclipse 940 GPU based on the RDNA 3 architecture.
Samsung Exynos 1480 SoC will receive Xclipse 530 GPU
As for the processor part, the new platform will receive four large cores with a frequency of 2.75 GHz and four small ones with a frequency of 2.05 GHz. What exactly these nuclei are is still unknown.
In Geekbench 6, the new SoC scores 882 and 2808 points in single-threaded and multi-threaded modes, respectively, but this is even less than the Exynos 1380, so the results are hardly worth paying attention to.