I tried everything that's why I think must be something related to 006c.
Those aren't facts. You shot down everyone who gave advice with nonsense like that.
If you want objective advice don't bias it with your own opinions.
I have nothing to add to the good advice you've already dismissed.
Did you bother to read all of the comments? As I already said I have RX 580, RX 570 and 3 5700 XT (14 GPUs in total). All cards running on risers 006c. All of the GPUs running fine except the 3 5700 XT which have random glitches. Changed everything: cables, risers (but always 006c), PSUs nothing worked. Do you think this is an opinion or a fact?