Does this mean my Neo geo is toast?

Terrella

Twinkle Star Sprite
Joined
Sep 22, 2022
Posts
38
Bought a cart off eBay listed as not working. Placed it in my analogue cmvs. Got garbled graphics and sound. Cleaned the cart and tried it again. Got the image below. Now this is all I get with working carts or no carts. Did this cart blow something?
F7D2E8E6-4237-4F2C-B163-0F070234A1D5.jpeg
 

hatmoose

Kuroko's Training Dummy
Joined
Dec 3, 2021
Posts
79
No commentary on Analogue CMVS except - motherflower they are expensive - I had no idea such a thing even existed.

Normally I have a pile of crappy but working 1-slot boards for testing. Never know what weird and wonderful errors I'm going to get from untrusted carts, poorly executed boots, dodgy z80 test carts and other razorblades left over from the 80's in someones box of spares.

As for what's going on. That screen looks like the "I can't boot" screen.
Sometimes it will be static - couldn't boot so gave up - normally you get this of one the critical chips is missing altogether, or so badly damaged that it's doing nothing.
other times it will be flick on and off, with the click of death through the speakers - nearly booted but the watchdog detected a problem and rebooted, normally in an infinite loop.

I'm struggling to imagine how any cart could cause this much damage. Maybe a failed bootleg where they wired +5v right onto the address bus or something? Maybe some disgruntled arcade service tech in the 90's made a sabotage cart to mess up his boss? Starting to sound a bit paranoid...

If you wanted to open the suspect cart up and take some pictures of the boards (both boards, both sides) there might be some clues as to what happened, and what to do next.
 

maki

Krauser's Shoe Shiner
Joined
Jan 1, 2022
Posts
231
yeah thats how it looks like when the BIOS or CPU ain't working, for whatever reason

I'd recommend to clean the slot on the MVS itself

pics of the cart would help, same for Analogue CMVS PCB, I have a strong suspicion that they'll be using the same rotten MVS as the rest..
 

Terrella

Twinkle Star Sprite
Joined
Sep 22, 2022
Posts
38
yeah thats how it looks like when the BIOS or CPU ain't working, for whatever reason

I'd recommend to clean the slot on the MVS itself

pics of the cart would help, same for Analogue CMVS PCB, I have a strong suspicion that they'll be using the same rotten MVS as the rest..
Bingo! Forgot they use the over the chip bios. It wiggled loose. Popped it back in and my system (guess I should not use cmvs) works again. Many thanks.
 

Terrella

Twinkle Star Sprite
Joined
Sep 22, 2022
Posts
38
No commentary on Analogue CMVS except - motherflower they are expensive - I had no idea such a thing even existed.

Normally I have a pile of crappy but working 1-slot boards for testing. Never know what weird and wonderful errors I'm going to get from untrusted carts, poorly executed boots, dodgy z80 test carts and other razorblades left over from the 80's in someones box of spares.

As for what's going on. That screen looks like the "I can't boot" screen.
Sometimes it will be static - couldn't boot so gave up - normally you get this of one the critical chips is missing altogether, or so badly damaged that it's doing nothing.
other times it will be flick on and off, with the click of death through the speakers - nearly booted but the watchdog detected a problem and rebooted, normally in an infinite loop.

I'm struggling to imagine how any cart could cause this much damage. Maybe a failed bootleg where they wired +5v right onto the address bus or something? Maybe some disgruntled arcade service tech in the 90's made a sabotage cart to mess up his boss? Starting to sound a bit paranoid...

If you wanted to open the suspect cart up and take some pictures of the boards (both boards, both sides) there might be some clues as to what happened, and what to do next.
As for the “razor blade” here are the pics
4FC904DA-1B01-4EEA-BAB1-A0D43B938544.jpeg
83B4EA89-63DA-49B8-97B4-89FEDD515E46.jpeg

What is this monstrosity? What are the bridging and why? Could be the key to fixing this cart.
 

maki

Krauser's Shoe Shiner
Joined
Jan 1, 2022
Posts
231
Bingo! Forgot they use the over the chip bios. It wiggled loose. Popped it back in and my system (guess I should not use cmvs) works again. Many thanks.
Glad that helped, thats the positive here :)

what you're describing is not a "premium product", sadly so, but thats not on you
 

GohanX

Horrible Goose
20 Year Member
Joined
Sep 28, 2001
Posts
12,058
Bingo! Forgot they use the over the chip bios. It wiggled loose. Popped it back in and my system (guess I should not use cmvs) works again. Many thanks.

Yeah those sometimes wiggle loose after several years. I just had to fix my old one, it was held in place with a little hot glue but when I disturbed it that was it, it never seated well again and would pop off slightly when changing carts sometimes. I ended up replacing it with a little SMD chip the other day so I never have to worry about it again.

That blue capacitor is attached to voltage and ground on that chip, so it's being used as a decoupling capacitor. I don't know enough to tell you why it would be needed. Make sure those legs aren't touching anything else though, if they made something short when the shell is on that could be the problem right there.
 

AppleiDog

Mai's Tabloid Photographer
15 Year Member
Joined
Nov 20, 2005
Posts
2,137
AP3mmjn62w9hmBGeZEEnzA_r.jpg
Screenshot_20221207-071408_Opera.jpg
 
Last edited:

Lach

sweet berry wine
15 Year Member
Joined
Feb 13, 2005
Posts
20,276
That's it you have to burn it now.
 

hatmoose

Kuroko's Training Dummy
Joined
Dec 3, 2021
Posts
79
As for the “razor blade” here are the pics
View attachment 61189
View attachment 61190

What is this monstrosity? What are the bridging and why? Could be the key to fixing this cart.
That looks like a ground decoupling cap to me. Although weirdly I don't think this is a failed bootleg - those are printed up like genuine mask roms. As others have pointed out, looks like its spent the last 10 years at the bottom of a well or something, corroded AF.

I'd be strongly dis-inclined to try and repair that cart, especially if the only test equipment available is a $600 MVS board. Loads of tested and working game carts at reasonable prices from reputable sellers on the buy/sell forum.
 

Neo Alec

King of Spammers
20 Year Member
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Posts
10,264
If it were me, I'd clean it up best I can and reflow the major solder points. Not risky.
 

hatmoose

Kuroko's Training Dummy
Joined
Dec 3, 2021
Posts
79
This is normal for multiple games. Check mvs-scans.com

The coalmine cart is Aerofighters 2: https://www.mvs-scans.com/index.php/File:Aero_fighters_2_set2_b1_front.jpg
That is quite a good game, If OP were going to spend some time on it maybe something like this?
0) clean it
1) dump roms and compare to MAME set
2) probe the pins on Neo ZMC https://wiki.neogeodev.org/index.php?title=NEO-ZMC
3) Probe the pins on PCM https://wiki.neogeodev.org/index.php?title=PCM
4) probe the pins on NEO 273 https://wiki.neogeodev.org/index.php?title=NEO-273
 

Neo Alec

King of Spammers
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