Red screen Processor Mismatch after switching brain box

[wilm245]

One of my G23's has been possessed with demons ever since the day I bought it 4 years ago.  I have been able to eliminate most of them, and that wouldn't have been possible without the resources I've found on this site and the advice shared by some very knowledgeable and generous members here so many thanks.  If I hadn't found this site I feel certain that many of the issues I have encountered would have caused me to believe that I was dealing with something that was too complicated and above and beyond my technical abilities, and ultimately given up and walked away from something i'm passionate about.  On to my current issue...

Shortly after midnight last night when many people were ringing in the New Year here on the east coast-my G23 with a history of demons decided to act up and throw a board monitor tilt, 3.3v out of range.  It was not the first time the machine has done this, but it had been over 6 months since the last time it happened.  This time was different because unlike the previous times when it happened opening and closing the main door would not make it disappear, turning the reset key did nothing, and inserting the ekey did nothing other than the machine saying it was verifying ekey and that message would disappear without opening the system screen.  Power cycles did nothing.  It was one of those errors/tilts that no matter what you try nothing seems to work.  I have a feeling everyone who has ever owned a G23 or other AVP machine has or will experience a seemingly unsolvable situation at some point.  I have experienced several, and last night was an unexpected and frustrating issue to start off 2024 and it didn't help that things already were chaotic around my house.  My crazy nextdoor neighbor had spent over $5000 on fireworks, which he does 3 times a year- New Years, 4th of July, and his birthday.  He started shooting them off around 3pm yesterday afternoon and at the time my machine tilted he was blasting off multiple mortar tubes simultaneously back to back, rattling all the windows in my house, shaking the pictures on my walls, and my dogs were going nuts, freaking out and barking nonstop.  I had to step away from all the nonsense so I left and went to a small sports bar that's just a few blocks from my house for a cocktail and to contemplate my next move.  While I was there I decided I was going to try something that had previously been suggested when troubleshooting my machine, and that was to take the brainbox out of my gremlin cabinet and put it in my good cabinet.  I stayed at the bar for around 2 hours hoping that my disruptive neighbor and barking dogs would be settled down once I returned home.  On a positive note, just before I decided it was time to head home I decided to stick a $20 in an "unregulated gray area skill machine" and hit for $750 on my second spin.  That greatly improved my outlook for 2024.  I collected my winnings, settled my bar tab and headed home to tinker with my gremlin.  I didn't know what was about to happen but as the title of this post says, when I put my gremlin brainbox in my good cabinet I was greeted with the red screen non-recoverable error, processor mismatch.  I did not turn the key, just shut off the machine and went to bed.

Today I did not touch the machine.  I have done some research and read some old posts here on NLG where other members had this issue.  From what I gathered the EPROMS on the backplane have to be mated with the MPU and that is what caused the red screen non recoverable error.  What I don't know is this:

1.  If I take the gremlin brainbox out of my good cabinet and put it back where it came from will it still be mated with the original eproms, and will I have to wipe non volatile storage and reconfigure?
2.  Did this error have any affect on the eproms in my good cabinet?  If I put the good brainbox back in the good cabinet and turn it on what should I expect to happen?
3.  Lastly, what would have happened if I had turned the key when I got the red screen?  Would I have been able to wipe the non volatile storage using the ekey and diagnostic, and then configure the machine?
4.  Would doing that clear the eproms and "remate" them with the mismatched board?

Thanks for reading and Happy New Year!

[Tilt]

Sounds like a fun neighborhood if you're young and like that kind of stuff ha ha.  On the bright side at least you got won some cash for your inconvenience!

Yes, that's what happened.  The brainboxes (CPU) serial number (and other game settings) are mated to the EEPROMs on the backplane.  When you turned it on it saw that the processor ID (unique to each brainbox) had changed and gave you the red screen letting you know that.  If you would have turned the key it would have updated the backplane EEPROM with the new processor ID, and probably some other information as well and then eventually booted up with a screen that says "No game enabled".  From there you'd have to set up the machine and re-enable your games again.  Since you didn't turn the key you should be able to put the original brainbox back in and the machine should boot normally.  If you want to move brainboxes between machines move the brainbox and the two EEPROMs as well and then you should be ok.  Make sure to keep them in order.  One is on top the other on the bottom.

The 3.3V out of range is an error message indicates the 3.3V power from your ATX power supply is out of tolerance.  It's the card that sits on top of or inside of your brainbox.  It converts +12V/+24V into the various voltages the brainbox needs.

My G23 blew a 440W power supply last night, so you're not alone ha ha.

[wilm245]

Thank you. I put my good brainbox back in my good cabinet, connected everything and it booted just fine, although it definitely seemed like it took about 4x longer than normal lol.  Now I have shifted my focus to this 3.3v out of tolerance error.  Is this the board you are talking about that converts to 3.3v?  And would this harness with the yellow and black wires happen to be 3.3v? Pictures are attached

[rickhunter]

No, Thats CPU +12v.   The 3.3v line is in the 24 pin connector.  See atx wire diagram.

[wilm245]

Thanks for the pinout diagram.  I disconnected the harness from the main board and the ATX power supply.  The connections were on there pretty tight and it took a good bit of effort to get them carefully disconnected without damaging something.  All of the pins on the main board and the power supply look brand new and looking through a magnifying glass all of the female connectors inside appeared to be in good condition inside the molex connector and none of them felt like they were loose or had any play.   I tested the ohms for all the wires on that harness and each on of them had the exact same reading.  I'm not really sure what else I should inspect at this point...

[Tilt]

Yes, that's the ATX power supply board.  If the 3.3V is out of tolerance then something is starting to fail on it.  I have a few NOS ATX power supply boards if you want to replace it.

[rickhunter]

I would add that there's a known issue that causes the board monitor tilt and it has to do with the 24 pin power cable.  Apparently the material used for the pins on some of these cable reacted with the material on the mating connectors and caused connectivity issues.  IGT recalled this cable to replace it with one made out of different mating material.  The problem can be fixed by swapping this cable with a known working one or use detoxit or some contact cleaner to clean the oxidation from the contacts.  The solution is kind of temporary since the chemical reaction will continue to happen after the cable is cleaned, but it will probably hold you over for a couple of years or more until you have to do it again.  There's also the possibility that has been raised here that the ATX power supply board is going bad and causing the issue.  In my case it was the cable, I just replaced it with a known working one.  I then cleaned the old one with detoxit and I have subsequently tested the cable with no issues, although it hasn't been used on a long term basis.  It is a relatively easy fix, just make sure you clean both ends of the cable and where it mates on both sides.

[wilm245]

I would add that there's a known issue that causes the board monitor tilt and it has to do with the 24 pin power cable.  Apparently the material used for the pins on some of these cable reacted with the material on the mating connectors and caused connectivity issues.  IGT recalled this cable to replace it with one made out of different mating material.  The problem can be fixed by swapping this cable with a known working one or use detoxit or some contact cleaner to clean the oxidation from the contacts.  The solution is kind of temporary since the chemical reaction will continue to happen after the cable is cleaned, but it will probably hold you over for a couple of years or more until you have to do it again.  There's also the possibility that has been raised here that the ATX power supply board is going bad and causing the issue.  In my case it was the cable, I just replaced it with a known working one.  I then cleaned the old one with detoxit and I have subsequently tested the cable with no issues, although it hasn't been used on a long term basis.  It is a relatively easy fix, just make sure you clean both ends of the cable and where it mates on both sides.

Good know.  I don't think that is the case with my machine because I closely inspected (with a light and magnifying glass) all of the pins both male and female on both ends of the harness and the boards they connect to.  All of the pins looked shiny and new, no visible signs of oxidation or corrosion and all of the harness wires had the exact same ohms reading from end to end.  But you never know for sure so while i'm at it i'm going to swap harnesses with my other G23 and see what happens.