Good choice of brand PSU.
Same problems in this MTB log as in the log in your reply #31 and being that you have done a clean install of Windows it points more towards the GPU drivers or the GPU itself.
From Speccy and probably the cause of your issues;
3/24/2020 Advanced Micro Devices, Inc. - Display - 26.20.13002.133
Advanced Micro Devices, Inc. Display driver update released in
August 2019
Use the free versions at the following two links.
Stress test your GPU with Furmark
Check your FPS etc with SUPERPOSITION
Same problems in this MTB log as in the log in your reply #31 and being that you have done a clean install of Windows it points more towards the GPU drivers or the GPU itself.
From Speccy and probably the cause of your issues;
3/24/2020 Advanced Micro Devices, Inc. - Display - 26.20.13002.133
Advanced Micro Devices, Inc. Display driver update released in
August 2019
Use the free versions at the following two links.
Stress test your GPU with Furmark
Check your FPS etc with SUPERPOSITION
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