Donkey Kong Graphics Issue

[WarLordAG]

I have a 4 board DK I've been fighting with since I got it. I've been able to clean and reseat the socketed chips up until now and it would last for anywhere from 3 to 6 months without messing up and needed reseated again.

Now it doesn't matter, it does it as soon as it starts up, even after a cleaning.
I have a picture of the title screen and the chips I believe may be suspect based on a visual inspection, but I'd like to know what these particular chips do and if they could in fact be the problem. I've also got a video.

I want to get this taken care of asap, as I've been on a tear repairing games over the last couple weeks and this is the last game that isn't 100% in the arcade.

 

[SanTe]

Hmmm, tough one. Here's a good DK troubleshooting page:

http://www.brasington.org/arcade/tech/dk

Bad 7C, 7E, or 7F?

 

[mecha]

Hmmm, tough one. Here's a good DK troubleshooting page:

http://www.brasington.org/arcade/tech/dk

Bad 7C, 7E, or 7F?

good resource.

mine would actually lock up once it would go into the demo mode of the gameplay. then eventually it was a sea of 0's. I had a few ICs, particularly the CPU, that had a bunch of corrosion on the legs. sandpaper took care of it very effectively.

I also went a step further and bent the chip legs inward a little more than normal so they would fit tighter in the socket. must have been the right thing to do, cause now the game works well.

mine's a 4 board too. took the whole thing apart, pulled every socketed chip, cleaned, reseated, reconnected the boards/cables, etc.

good luck sir.

 

[CrazyKongFan]

mine would actually lock up once it would go into the demo mode of the gameplay. then eventually it was a sea of 0's. I had a few ICs, particularly the CPU, that had a bunch of corrosion on the legs. sandpaper took care of it very effectively.

Just out of curiosity, did it have any holes that allowed Mario to fall thru? I've got a 4-board set with graphic issues, and one of them is holes in the beams. When Mario falls thru the floor, the board clears and the game doesn't know how to handle that in demo mode and locks up (if I start a game before the demo mode appears, it clears the board if you fall thru the hole and goes to the rivet level, which also has a bunch of holes in the beams)

 

[hindered]

It's possible the chips themselves are fine, but need to have the code re-written to them. I was having issues with random resets, jumpman warping to the top of the girder level, random board freezes etc. I pulled and dumped my CPU ROMs. Turns out 5B and 5E failed to match up to anything in MAME's romident. So, I reprogrammed the chips and now everything's hunky dory.

 

[WarLordAG]

I never followed up on this, my buddy had a spare 4 board set he sold me instead.

I'm going to replace the sockets and chips themselves at some point and I'm 99% sure it'll fix the issue.