Question PC crash but still turn on, screen stop receiving signals when gpu hard working

Jun 25, 2020
I have a problem similar as:

BIOS drivers are updated as well as software radeon is. PC has been working well since october last year, I can use the pc but I cannot request the gpu to work (open serious videos, playing videogames or benchmarking), when I try to benchmark or when I try to play a videogame or open several videos, the screens suddenly stop receiving signals and my computer continue sound for a while (10 seconds more or less), then it also stop sound, meanwhile nothing change inside the case, lights and leds are as usual fans are working as usual all ok, except I can't do anything but turn off (holding the turn of button for some seconds).
All the components has less than a year
Mi PC:
motherboard: MSI x570 A-Pro
graphic card: asus arez strix rs vega 56
cpu ryzen 3600
ram two asgard 8 gb 3200 16 18 18

I tried to stress cpu and all its ok
I tried removing one or another ram modules and the problems remain with each of the ram modules. I even tried with another rams and the problems also remain.
I switched the gpu from one to another motherboard slot the problems remain.
I observed some dark mark in the gpu PSU pines and also in the psu wires that aliment gpu.
I tested GPU in a friends pc and it runs perfectly

I think that a couple of times the problems occur in bios set up.

Thanks for read
any advices?