Thanks @acebathound , I appreciate that write-up. Sadly, pressing the daughter board doesn't help at all, so I guess there's a solid that's that's not it.

I've pulled the board several times since I installed the socket, and tested everything. It seems good, but maybe it's worth a third go around. I'm pretty sure I've checked every possible mistake/issue, and "beeped" out everything with my meter, but it won't hurt to do it again. Perhaps some pics wouldn't hurt, since it will give everyone a chance to see if I'm visually missing anything. I even searched the board for solder splashes and such, no luck.

Not sure how I would have, so hopefully not. All I did was remove the RAM / battery, and install the socket.

No luck so far. Debating pulling the RAM socket and trying again, but I'm a little worried about the fragility of these pads/traces with multiple attempts going at them.

Cleaned all the edges and connectors again, made sure everything was making good contact, no change. Frustrating

barakandl thank you for that info, I'm game to run through what you said, but I'll be honest, I got a little lost in there. It sounds like you were suggesting two things:

1) Check continuity between the 5101 and the 6502 / Piggyback chip. I was trying to figure out where from the schematic section, but I'll be honest, it's a little confusing.

For example, I see A0 - A7 on the 5101 as pins 4, 3, 2, 1, 21, 5, 6, 7. They seem to be labeled as a group "A", which goes over to AB0-AB10, BAB11? Which then heads over to the 6502 A0 - A11, pins 9-20? I'm a little confused there, my apologies. I'm pretty good with schematics usually, but chip-to-chip stuff and the logic involved isn't as in my wheelhouse sometimes. I'm sure I'm just missing something simple.

2) Remove ROMs (not sure which), turn the game on, and poke around with a logic probe? I'm a little unsure of what to do there. I have a probe, but I've only used it a handful of times on arcade games in the past. Happy to perform whatever testing you suggest, just a little more explanation/guidance would be awesome, if you have time.

Okay, makes more sense. I'll do some continuity testing today and report back.

Side question: I'm pretty careful about ESD and such, but is it possible I might have zapped it and messed something up? Never had an issue with that, but figured I'd ask as an aside.

Okay, just verified continuity as follows is all good. I tested from the top of the socket I installed at Z5. Here's where I tested to and from successfully for continuity:

Z5

Pin 1 = 6502 Pin 12
Pin 2 = 6502 Pin 11
Pin 3 = 6502 Pin 10
Pin 4 = 6502 Pin 9
Pin 5 = 6502 Pin 14
Pin 6 = 6502 Pin 15
Pin 7 = 6502 Pin 16
Pin 8 = GND
Pin 9 = 6502 Pin 33
Pin 10 = 6502 Pin 33
Pin 11 = 6502 Pin 32
Pin 12 = 6502 Pin 32
Pin 13 = 6502 Pin 31
Pin 14 = 6502 Pin 31
Pin 15 = 6502 Pin 30
Pin 16 = 6502 Pin 30
Pin 17 = Z4 Pin 10
Pin 18 = Z36 Pin 8
Pin 19 = Z36 Pin 2
Pin 20 = Z36 Pin 9
Pin 21 = 6502 Pin 13
Pin 22 = C11

So it seems I'm getting the connections I should to the next components in line, which leads me to think that my socket is installed correctly.

Thoughts?

Never had any issues with NVRAM, always been great. I'm thinking it's something else, given the fact that the socket connections are testing good. Hopefully someone has another suggestion on what to try next.

Yep, that was one of the earlier suggestions, that's been checked as well. There are several that are supposed to be connected, and they test as such. I even went through every combination just to be sure, and nothing is bridged that shouldn't be.

It's a longer thread... it was mentioned earlier that you can actually boot the game without RAM (another member tried and proved that was true). So even if the NVRAM was bad, taking it out would have let it boot, and that didn't work sadly. I also put the original back in, no change.

I don't have the reset board, never did, so that's not it either sadly.

Interesting, I saw the uncovered EPROM and wondered about the safety of that. I've seen plenty of games where the old cover was gone on these, but not one with a fluorescent light. I wasn't aware that might be an issue with those. I don't have a way to verify the ROMs or make a test ROM myself, but could probably get some help with that. With the ROM files not being readily available, what's the best method for that?

I removed the socketed reset piece, just to see if there was a change, no luck. Thanks for the suggestion though.

I know all the cabinet mods, but haven't done the board ones before. I'll happily do them, but perhaps some temporary jumpering for testing wouldn't hurt too, just to see if it's related. Or I guess I could test continuity to ground for various places, that wouldn't hurt either.

Would a ground issue cause it to not boot like this? Attract mode lights, but nothing else? My ground issues before were always different, so I'm curious.

Sitting solidly at 5.03V , I tweaked it slightly to 5.09V just for the heck of it, not change in boot.

If you mean the reset board, I don't have one. I never did, this game didn't have one when I got it (and it booted and played just fine).

If you mean the daughter board on the actual CPU board, I can't remove that (it's soldered on). I've tried all the "press on the daughter board" stuff and haven't have any change, sadly. I thought maybe, since the board was lightly resting facedown briefly during the socket install, maybe I screwed it up that way, but it seems unlikely, I was pretty careful.

I've was pondering using someone like Coin Op Cauldron (since cost is low even though lead times are a while). I also thought about buying the $50 PiggyDeux. Given that messing with the daughter board seems to do nothing, I'm not sure if that would be a waste of money. I hate when I can't figure out the issue, makes the decision making portion much harder ha.

Checked a bunch of board-related grounds, seem to have ground continuity, but I'll start working on that stuff just in case. I'm still wondering if repinning all the connectors is worthwhile? Seems like a crazy chore, but that's the only other major thing that was messed with.

Thanks, yep I mentioned that as an option earlier, and was debating it. I was hoping to narrow the problem down to that before spending $50. One of those situations where board repair would run me about twice that with a guarantee, so tossing $50 at a maybe seemed iffy without trying to figure out more first. Sadly not much luck with that so far, despite some great help and suggestions from everyone.

1) Yep that's where I test it, and it's within that spec

2) No, wasn't sure what exactly you wanted me to do there. Did you just want me to hook the probe to 5V, TTL, and test that pin and see what happens when I turn the game on?

It's always high, assuming I did it right.

I had it set on Pulse, TTL, hooked to 5V. Probe on Pin 40 of the 6502, turned the game on, immediately was High ("1" on my probe) and never changed. There *might* be a very slight flicker on the low just before it shows high, but we're talking less than 1/10th of a second, if that. I'm guessing the "low" I should be seeing is not that brief.

Let me know if I did that wrong.

I've been trying to find someone local with another 80B game I can do some swapping with, but no luck so far. gdonovan offered, but it's a couple of hours ride, which is tough given a busy schedule. I'm sure there's another game closer, but I haven't had much luck finding one so far.

PROM2 has been reseated a couple of times, no change unfortunately. I'll throw a sticker over that window as suggested!