PC PSU

["m_surgenor" <malcolm@xxxxxxxxxxxx>]

I splashed out on a Silentmaxx Fanless-Pro 503W PSU for my main PC
and it arrived today.  I swapped it out with my old unit but I can't
get it to work.  :(

If I press the PC power on button there is obviously power being
supplied as the processor fan spins up but as soon as I take my
finger off the power button it all shuts down.

I'm not sure what would happen if i kept my finger on the button but
I don't want to do that in case something's seriously wrong.

I've triple checked all my connections and can't see anything wrong.

I've pared the connections back so that only the m/b is supplied and
still get the same problem.

Anyone any ideas what I might have done wrong??  Or have I just got a
duff unit?

TIA

Malcolm