VLC 8825 Gopher Cash screen went black

[newkid3]

   I have a VLC 8825 Gopher Cash that I sent the board off and had the batteries replaced cleared and reprogrammed.  I have not had the machine on no more than a total of 4 hours total on and off since I got the board back just making sure everything worked. Well I got it all ready and took it over to my sisters house today to give it to her as a surprise. I got it over there and got it all set up and I played it for about 5 minutes. Then I went outside for about 15 minutes to tell my brother in law to tell my sister to come out that I had the surprise ready. I walked back in there building and looked over and the monitor was black. I could not believe it.
  So I turned the machine off and back on and nothing happens. Nothing comes on the monitor.
The bill validator never does cycle and I get no sound from the game. I am pretty sure the monitor is good because when I turn the power switch off the monitor flashes white which shows it had power.
  Has anyone seen this happen before? Any suggestions of what I need to check or how to go about checking it. I have no experience with these VLC machine so some help would be nice.
 I do have another machine and two more boards but both boards need batteries and reprogrammed. 
  I do think it is a board issue or something else in the cabinet but I am not sure.

   Thanks

[shortrackskater]

First, make sure the power is off!
Pull the MPU and check the connecting edges, then FIRMLY plug it back in and make sure it's fully seated.
Power up and see what happens.
If it's still dead... power back off and just look though the machine to see if any connectors came loose. Sometimes, over time things just work their way out.

[newkid3]

  I tried the board from the none working machine in my machine at home and it came right up and played good. So then I took it back over to my sisters to do some testing on power supply ect. Well I put the board back in it and turned it on and the game booted right up and we played it for over an hour. So I guess it was a bad connection. I thought I unplugged and plugged them all back in last night but maybe I did not. I guess it could have been some corrosion on one of the connectors and unhooking them one more time and plugging them back in might have cleaned it  up. I am not sure but I am sure glad it is working.

     Thanks