First surprise... It was full of cockroaches... Alive and dead.
2nd... There is a problem with the power supply. A badly soldered connection of the power connector (this I'll solve easily)
And 3rd and the most important, although for 8 and 3.5v everything is ok, it does not output a correct Reset signal.
It is 0v, and that means it will continually reset the PS (If it's still working).
How can I solve that?