CPS2 B Board problem

Hi to all,


I bought a Super street Fighter 2 Turbo CPS2 B board.

I connect it to my A board and the game run ok.
I switch off and re-switch on and now I get only a blank screen!

I try to switch off and on several times and finally the game runs correctly!


I checked carefully the connection between A board and B board; I cleaned both the boards.
After this, I opened the game board, to see the battery status; I get 3.67 Volts, so I think it's good (the game isn't died).

What could be the problem?

Thanks to all.

Just reseat the B board onto the A board, it does that a lot. Make sure you try to keep the B board flat when inserting it so you dont bend any pins on the A board.

I've had A/B combinations that did this -- having clips on them helped, they worked more reliably. Eventually I changed the A/B board combination with different hardware, and solved it.

I always Zip-tie my A+B boards together if i don't have any clips. seems to work fine.

Thank you to all!


I opened the B board and I attached the PCB directly to the A board.
Same result

I checked: no pins bended.

I tried to use this B board with another A board, but same result


I checked the right insertion of the EPROMs and I cleaned very well the B board; I removed the "up-board" of the B board (the little PCB connected up to the B board of SSF2T) and I cleaned the pins.

THIS IS VERY STRANGE:
I tried to run the B board without the "up-board" on both the A boards I have; it runs!! (without some graphic, but it RUNS!!)

But if I add the "up-board" to the B board, it doesn't run.
Why?

Thanks

Please, help me!