Replace logic board - Mactest result after recapping mac iici.

[crazyben]

when I connect the monitor to video card instead on on board video port that error went away. And the test result is same Bank B ram error.

 

[crazyben]

 

[joshc]

@crazyben Is that after removing the SIMMs that were in Bank B? I guess not as it sounds like that bank is failing still. Have you tried with the larger SIMMs in Bank A only?

The only thing you can do here is swap them between banks until you get no errors - but it's possible there are issues with both banks.

30 pin SIMMs are not that expensive, and you can still buy them from a variety of sellers.

 

[Phipli]

Have you tried with the larger SIMMs in Bank A only?

I think they only have 1MB SIMMs.

 

[Phipli]

The only thing you can do here is swap them between banks until you get no errors - but it's possible there are issues with both banks.

Hold up, we've already swapped them and a fault remained in Bank B.

Might not be the SIMMs.

 

[joshc]

Heh...hard doing this over a forum. Easy to talk about the same thing in two different ways.

Larger as in... physically slightly taller / more chips on it. He seems to have two variations of SIMM.

Has he swapped them? I don't see a post where he says he's tested with Bank A only, he just posted a diagnostic again that shows an error with Bank '2' which I assume is what Snooper shows when it means Bank B.

But yes, other things can cause bus errors.

 

[Phipli]

Has he swapped them? I don't see a post where he says he's tested with Bank A only, he just posted a diagnostic again that shows an error with Bank '2' which I assume is what Snooper shows when it means Bank B.

Fair point. I forgot that sometimes people don't actually do what you said.

 

[crazyben]

Sorry I was not clear. After swapping the RAM to Bank B still gave error.

 

[Phipli]

Sorry I was not clear. After swapping the RAM to Bank B still gave error.

Excellent, now it's important to know what happens with nothing in bank B. This tells us if it is just testing Bank B first, and you have a more global issue.

 

[crazyben]

With nothing on bank B get this error.

 

[Phipli]

With nothing on bank B get this error.

I suspect you have a more general logic board fault. Sorry, but it will be a nightmare to find. This type of fault that doesn't stop the machine from working is really hard to locate.

The only vague and unhelpful advice would be, it probably isn't the data bus, but it may be related to the address bus.

 

[crazyben]

Okay. I will keep and eye out for iici board. I will use this until it stops working. Thank you for your help on this.

 

[Phipli]

Okay. I will keep and eye out for iici board. I will use this until it stops working. Thank you for your help on this.

Oh, one last thing, do you have any cards in the machine? Pull them out. All nubus and cache cards.

 

[crazyben]

Took out all the cards and reran the test. And still getting bus error with no RAM in bank B.

 

[joshc]

https://68kmla.org/bb/index.php?threads/fs-macintosh-iici-motherboard-recapped-working-bay-area.45339/