Optiplex 9020 not working at all.

I was working on my computer, and some hardware here in the shack.

I am affraid an externa power supply is I use for the transmitters here made an Short to ground which was also connected to the PC.

It did not short the external power supply, but the fan's of the PC began to run at the highest speed and the PC turned off.

Since then the power button does nothing at all.
the BIST led will turn green when pushing the button and the FAN"s wil run at full speed.

It seems the 12V and 5V from the PSU are OK, but i am not sure which pen/wire of the PSU should have which Voltage.

I am affraid the problem exists in the main board and not in the PSU of the PC.

Anyone any idea's?

are there any points on the main board where i can measure if the correct power is connected to the correct points?