Problem with motherboard mvf1

konrad

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Hello, I have a problem with an mvf1 motherboard that does not start and has power. The red led is on. Could it be the power supply? Best regards
 

BIG BEAR

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What are you getting on the screen? Do you hear any clicking sound?
BB
 

konrad

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What are you getting on the screen? Do you hear any clicking sound?
BB
Nothing on the screen, only the power led is illuminated before, yes, I heard clicks. I have also tried to remove a cartridge and the checkered screen does not appear.
 

BIG BEAR

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Try making sure you bios chip is firmly in or swap it out for another one.
BB
 

konrad

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Try making sure you bios chip is firmly in or swap it out for another one.
BB
This is what happens on the original bios screen.
 

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maki

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thats how it looks when it can't boot, often caused by severed traces to the BIOS that aren't conducting when they should

best is to check the continuity of each pin/trace from the CPU to the BIOS, see attached pic, I use that as help when I have MVS with these problems

don't get confused by the different numbering systems (thats why I added the pins of the CPU on the BIOS IC)
one starts with 0, the other one with 1
oh well, best thing about standards is that there is so many of them..
 

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konrad

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Aug 20, 2013
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thats how it looks when it can't boot, often caused by severed traces to the BIOS that aren't conducting when they should

best is to check the continuity of each pin/trace from the CPU to the BIOS, see attached pic, I use that as help when I have MVS with these problems

don't get confused by the different numbering systems (thats why I added the pins of the CPU on the BIOS IC)
one starts with 0, the other one with 1
oh well, best thing about standards is that there is so many of them..
I have put the other larger motherboard and the same thing happens to me.
 

BIG BEAR

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The problem must be with that mini super gun you're using then.
Purchase a different device to plug your boards into.
BB
 

maki

Krauser's Shoe Shiner
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Jan 1, 2022
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forgot to say that a weak PSU can cause that as well IME, so yeah the supergun voltages should be checked
 
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