theres loads of posts with regards to mc boards and faults,for someone to tell you exactly whats wrong with it for a sure fire first time fix you would be wrong asking if thats what your looking at.
you should check all the volatges are right to start off with and owning 2 mc cocktail tables and only having 1 working board and 3 faulty ones i understand straight forward fixs are not 100% thats for sure.
i had 2 repaired by someone,they came back working and 1 went after 20mins and the other within 1 minute.same prob on 1 with green screen,white blinking screen on another and jailbars on the remaining one.
yes I was hoping for "hey, I had exactly the same issue! you have to replace that ram and there you go!" but I suspect it isn't so easy...so you didn't figure out in which area was your pcb repaired for the green frozen screen? I am using a known working cabinet so voltage source is ok, I would have to build an adapter to bench test it.
I think what you are seeing is just the screen burn of the landscape.
Looks like the board isn't even booting, or booting fully.
I've seen screens like that, that were caused b bad cpu's, bad voltages, bad rams. So you need to start eliminating stuff. Power is the first thing to start checking.
Looks like the same issue I am having. power is good 12 at 11.8, 5 at 5.1. Ar2 is rebuilt, new big blue, ohm all rom sockets, swapped cpu. Tonight I am going to pull all ram thats not in sockets and install sockets and ram.
Pulled out the logic probe and found the cpu active then started looking at the ram. I found that 3 chips did not act like the rest of them so I pulled them and installed sockets. After installing all new ram I had the same problem until I grounded the watchdog (which I had done before) and it came up. So I let it run for a bit and pulled the ground and it still came up... its ran for about 6 hours yesterday and 4 today without a problem. It must have been more than one piece of ram that was bad is all I can think of.... but its running, for now...
I had replaced three rams before (4116) which were missing the top and had loose pins...but nothing changed, where do you short the watchdog? I don't have the board with me now I will try later.