This is not a question, it's more a helpful hint for someone using 5600 XT.
If you have a "faster" version of 5600 XT with higher VRAM clocks in BIOS - downgrade to a "slower" one.
I bought Powercolor 5600 XT 6 months ago and I was struggling with green screens all this time. Every day I saw at least one green screen crash, usually more. Crashes happened at random, GPU load was not a factor. Nothing was a factor. Funny fact - I never had a crash while running Furmark stress test. There was one distinct sympthom - if you launch a 3D game you might see artifacts, horizontal bars with corrupted image. If those appeared it would mean you will 100% get a green screen crash pretty soon.
I've tried everything except modifying GPU BIOS. Nothing helped. Finally I flashed an original 1st gen BIOS from Techpowerup and it solved the crashes. So in my case a 14 GHz BIOS was the root cause.