This is a list of AMD GPUs known running together with OpenCL and Blender Cycles. It is composed by either personal experience or from sources on the web:
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║ GPU ║ OS ║ OS version ║ Blender v. ║ Driver ║ Source ║
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║ Radeon cards ║ ║ ║ ║ ║ ║
║ RX580 ║ Xubuntu ║ 18.04.02 ║ 2.8beta ║ OpenCL-Pro ║ 5 ║
║ RX580 ║ Linux* ║ N/A ║ 2.79 ║ N/A ║ 1,3 ║
║ RX470 4GB ║ Kubuntu ║ 16.04 ║ 2.78 ║ AMDGPU-Pro ║ 2 ║
║ RX Vega 64 ║ Arch, ║ N/A ║ 2.79 ║ AMDGPU & ║ 4 ║
║ ║ custom kernel, libdrm downgrade ║ AMD OpenCL ║ ║
║ RX480 ║ Linux* ║ N/A ║ 2.79_build ║ N/A ║ 3 ║
║ RX Vega 56 ║ Linux* ║ N/A ║ 2.79_build ║ N/A ║ 3 ║
║ RX Vega 64 ║ Linux* ║ N/A ║ 2.79_build ║ N/A ║ 3 ║
║ RX Vega Frontier E. ║ Linux* ║ N/A ║ 2.79_build ║ N/A ║ 3 ║
║ Pro WX 7100 ║ Linux* ║ N/A ║ 2.79_build ║ N/A ║ 3 ║
║ Pro WX 7100 DUO ║ Linux* ║ N/A ║ 2.79_build ║ N/A ║ 3 ║
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* likely Ubuntu or a derivate (officially supported), see this comment. Also means that AMDs OpenCL implementation must've been used, as there's no other known working so far
sources:
1,
2,
3
4: user gandalf3
5: myself, using Xubuntu 18.04.02 with an all open stack (standard) plus the OpenCL portion from the closed AMDGPU-Pro driver
This list is obviously far from complete, it's just meant as a start. I'll gather more and more information in the near future.
Feel free to edit, improve and add to this list to complete it and make it comprehensive in the end!
P.S.: The table was made with https://senseful.github.io/text-table/, as the standard SE markdown does not support tables in any way, see here.