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SE/30 Garbled screen
Posted by: lubert on 2019-05-21 08:53:31
I bought an SE/30 which had the Simasimac symptoms, so I got the logic board recapped. The mac boots successfully now, however the screen has a strange flickering and garbled display. Any ideas what could be the culprit?

IMG_20190521_084745_exported_stabilized_3669444063718540044.gif
Posted by: Bolle on 2019-05-21 13:13:16
Could be caused by an intermittent connection of an address line on one of the video address muxes (chips UA8 to UD8)

I had this exact symptom on one of my SE/30s and it took me ages to find because all address lines buzzed out fine on the first two tries but it was open when I went through everything a third time.

Also could be one of those chips is on its way out.
Posted by: lubert on 2019-05-25 11:53:35
Thank you @Bolle for your insight, I will try to check all the address lines. If one of them does have an intermittent connection, what's the appropriate fix?
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