Elfen, I think you are mixing this thread and another one in your thought process there.

Vertical Line's is probably ram,  not to say there isn't also some issue with the A/B.

A bright horizontal line in the middle is usually the A/B yes with the 128k, 512k, Plus.  

With the SE/30, a bright horizontal line, or no video is usually an issue with cap goo rotted UE8 on the MB.