Newly acquired Mac SE with screen issue

[acerocknroll]

Hi everyone, to build on my post over in the Conquest section here is my newly acquired Mac SE! It seemingly has had some upgrades like a 500MB HDD and 8MB of RAM, maybe some other stuff?



Condition is overall pretty good, and it boots and runs fine. The first time I powered it up the screen display was 100% perfect, no issues. Unfortunately, it's developed a weird video issue that seems to be getting worse each time I start it up so I'm trying to figure that out before I play around with it any more. It's not displaying certain pixels, and is especially apparent when there is a large block of black pixels present (especially on the shutdown screen). Here's an example:



You can see it clearly on the RAM use bar next to System Software but it's all over the place sadly. Here's a video that will hopefully be helpful:

https://youtu.be/LWQh9xyfnew

I've looked at the repair guides pinned here but I'm not really sure what to even call this issue in order to diagnose it. Any advice on where to begin would be hugely appreciated, thanks!

 

[jimjimx]

Try reseating the rom simm.  If that doesn’t work go through the ram and do the same. 

At first look, I thought you said that you had a SE with 8 MB, but the SE can only have up to 4MB..

 

[dochilli]

Thats an upgraded SE with a SE/30 mainboard.

 

[jimjimx]

Thats an upgraded SE with a SE/30 mainboard.

Great! Now how do we fix it?

... And I think you mean Digital board. The Macintosh SE and SE/30 never had a main board.

if there was a main board, it would be the analog board, which powers everything. 

 

[Scott Baret]

If it's an SE/30, which it definitely is, you need to replace the capacitors on the logic board.

An SE/30 board will fit perfectly inside a regular SE. You may want to check your floppy drive to see if it was upgraded to a 1.4MB drive. Pop in a known good high density disk (if the drive is clean and working) or look for a blue label on the side of the drive. (800K drives have either red or black labels).

To briefly and simply define the boards:

The logic board is the horizontal board which contains the CPU. We can also refer to it as the motherboard. The RAM, ports, and controllers are all here.

The analog board is the vertical board to which the power supply is mounted in an SE or SE/30. On some models, this can be called the "power/sweep" board.

There is also a smaller video board which connects to the back of the CRT, although this attaches to the analog board. The analog board has some video circuitry on it, plus it has a power connector for your hard drive.