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(SE/30) 2 mainboards both have Simasimac after recapping
Posted by: Yuffi_ on 2020-07-25 07:21:30
Hi there,

Recently, I picked up two SE/30 boards to repair.

So far, I’ve been having trouble repairing them as both seem to have Simasimac even after cleaning and recapping them.

One of the boards has the early stages (artifacts across screen) with death chimes while the other one has zebra bars and no chimes whatsoever.
 

Both persist even when ROM and RAM are pulled out, both have no batteries, and both persist after resetting (both power and buttons on board) 
 

What steps should I take next? 

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Posted by: erichelgeson on 2020-07-25 08:05:51
Do you have known good ram your testing with?
Posted by: Yuffi_ on 2020-07-25 08:32:12
Do you have known good ram your testing with?
Yes, the RAM I am using is known good.
Posted by: Yuffi_ on 2020-07-25 09:24:45
Update: ROM was bad, don’t have any other ROMs to test with. Will have to find another ROM stick.
Posted by: Yuffi_ on 2020-07-25 09:25:30
I’m pretty sure IIfx or whatever ROM isn’t supposed to sad Mac Chime and then show this on a IIsi.

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Posted by: ttb on 2020-07-26 02:27:25
UE8 looks pretty rough on both of these. Have you checked continuity between the tops of each pin and another point on the board it connects to? This effort here should be useful in that regard:
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