Mac PRO 4.1 (5.1) help

[kmg1974]

I have a classic Mac Pro (cMP) 4.1, upgraded with firmware to 5.1
it has an NVME PCI-e adapter card with the startup disk, and a R380 video card
it has dual core E5680s, and 40 GB of RAM

It was working fine last week. This week I moved it downstairs as I wanted to work on it, and it bumped onto the landing (not too hard, but still a bump).
When I tried to start it up again it stayed off
The board is getting power and also stand by (using the diagnostics button), but when I try to short the startup it does not start up.
I have taken the computer apart, cleaned the connectors and made sure they were reseated properly. (I have not removed the processors from their heatsinks) , but based on the Mac pro technician guide it should start up if I short two pins, but it doesn't.
Is there anyone that could guide me through trying to get the computer to work again?
thanks

[Daedalus]

@kmg1974: zoals je misschien wel hebt gemerkt is dit een Nederlands forum. We verwachten dan ook dat je je vragen in het Nederlands plaatst. Bij hoge uitzondering staan we ook Engels toe, maar dan verwachten we wel dat je Nederlands kunt lezen en begrijpen.

Dit topic gaat dan ook op slot. Je mag een nieuw topic openen in het Nederlands. Vul dan wel de template in die je krijgt. Mocht je desondanks in het Engels berichten willen plaatsen, stuur mij dan een DM