I just received upgrade CPU (L2.1) and Sound Rom (L1.1) chips for my Congo. The CPU is marked G11 - I know where this is and how to change it. However, the Sound Rom is marked U2 but I can't find U2 on the WPC Audio/Visual Board. Is the sticker on my chip just mislabelled? Can anyone tell me which chip needs to be changed please?

I have changed ROMS many times but this is my first time on a WPC95 system.

Thanks.

I suspect the Sound Rom should have been labelled S2. Can anyone confirm my suspicion that it is the Congo S2 Rom that should be upgraded/changed?

Thanks. OK I changed the ROMS and I get nothing. Just a Black DMD, no sounds, nothing. Put the original ones back in and everything is fine. The game even kept the settings which I thought was weird because usually the settings get deleted right when you attempt a ROM upgrade? I have done many ROM upgrades in the past and have never had an issue. Does this seem like one of the ROMs is bad?

Now I am wondering if I waited long enough for the game to boot after I turned it on. Does Congo take longer to boot (display info on the DMD) with the most recent ROM version? Not sure I want to try the new ROMs again in case they are bad - If they are could it damage the game? No they were not inserted backwards - I was very very careful about that.

Figured I should update this thread with the solution. It turns out that the CPU ROM was bad. The image was burned on a chip that was too small. Apparently a few WPC games required larger chip sizes to hold the image.

Problem solved. Thanks everyone.