Desktop won't turn on. I've been swapping between 2 motherboards (different makes) and 2 power supplies with the same strange faults. As soon as I connect to power all the fans start spinning, nothing at all on the screen , power and reset buttons do nothing at all, so can't even turn off the fans unless I pull the power cord out, I know that at least 1 of the motherboards and 1 of the power supplies were working properly, has it being damaged in my attempts? . Any idea please?