dead 4 slot?

MasterAmado

MasterAmado

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when I turn my cab on all I get is a jumble of green and white squares on the monitor. It displays the same thing whether I have any mvs games plugged into the motherboard or not. The cab works fine with my cps2/cps3 games. I had not played any neo geo games in a few months but the four slot was working fine last time I used it. There seems to be no visible damage to the board and I reseated the motherboard just in case but the problem remains. :crying:

 
mainman

mainman

CPS2 Person.,
20 Year Member
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Mar 26, 2001
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3,879
If it worked fine not to long ago but magically decided to give you the finger you either have bad ram or a solder joint broke around one of the custom chips.
 
channelmaniac

channelmaniac

Mr Neo Fix-it
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My guess would be a leaking battery ate a trace in the control circuits for the backup RAM. If the control lines for the backup RAM aren't working right then the game will be dead.

It's possible to have a bad Work RAM do that, or a bad solder joint on a surface mount IC, but if the board hasn't been moved and flexed lately the odds of the solder joint being the issue are low.

If you don't want to tackle the repair yourself, I do repairs on them.

RJ
 
MasterAmado

MasterAmado

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channelmaniac said:
My guess would be a leaking battery ate a trace in the control circuits for the backup RAM. If the control lines for the backup RAM aren't working right then the game will be dead.

It's possible to have a bad Work RAM do that, or a bad solder joint on a surface mount IC, but if the board hasn't been moved and flexed lately the odds of the solder joint being the issue are low.

If you don't want to tackle the repair yourself, I do repairs on them.

RJ
Click to expand...

How difficult would it be for me to repair it myself? I don't have a lot of experience repairing pcbs but I have done a fair bit of soldering in my time.
 
channelmaniac

channelmaniac

Mr Neo Fix-it
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It's a matter of tracking down where the problem is.

Take the boardset apart and use a logic probe to check the CE*, OE*, and WE* lines on the backup SRAM ICs. If any signals are missing then you found your culprit.
 
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