If someone could help with this issue
System was working perfect for a year without any changes.
Then after I carefully transported it to another place it shuts down in around 10 sec after start.
And the PSU keeps working.
As well the system starts without Power swith even being connected to the front panel, just after turning the PSU on.
So far checked the Videocard, different PSU, battery out-in. Maybe it is usefull to mention that when I plug out the PS connector from any of the CPUs, the system starts without turning off with the another remaining CPU, but showing nothing on a screen.
Maybe someone could help with that, I would be very greatful.
The local service charged me 55 euros for looking inside and just said-something with the MB, buy a new one, not really helpful.