I am sure the problem is from the PSU. Who can confirm?
No one can confirm.
To confirm and be pretty sure you need to put a different psu into the rig and if the rig works most likely your psu is bad.
even that test is not quite good enough . Since you could simply have a bad cable on the lepa.
to confirm perfectly you need to take every cable on the lepa and use a meter to see every pin to socket is good on every cable.
you then need to have a second rig that works with a different psu.
then put the lepa in and see if the second rig works
if the second rig does not work the lepa is most likely toast.
MY guess is the lepa is the issue but that is a guess . not a confirm.