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Macintosh SE - memory size switching resistor

Aektann

Well-known member
Hi all,
I have a perfect working Macintosh SE which came to me with 4mb of memory installed. System 6 shows all 4 megabytes in the “About this Mac“ correctly. The main question is: do I still need to cut the R35 resistor as it is documented for my revision of the motherboard?D084C354-FF14-4160-8E77-A9E83416D09F.jpeg
 

desertrout

Well-known member
Curious. I wonder if the resistor is bad?

To answer your question, if it's working it's working. But I personally would clip the resistor because that's what you're supposed to do... and to avoid any potential issues (though, if the system is recognizing the memory, I can't imagine what the issues would be...).

Weird!
 

LaPorta

Well-known member
I agree. Also...might want to hack out or desolder that battery before it potentially explodes on you.
 

Aektann

Well-known member
Curious. I wonder if the resistor is bad?

To answer your question, if it's working it's working. But I personally would clip the resistor because that's what you're supposed to do... and to avoid any potential issues (though, if the system is recognizing the memory, I can't imagine what the issues would be...).

Weird!
Well, I was curious if the system could be showing all the memory but using only a part of it. Sounds stupid, I know. Ok, I’m gonna clip the resistor when I unscrew the case next time.
 

cheesestraws

Well-known member
Sounds stupid, I know

Nah, it doesn't sound stupid, it's the kind of thing that computers, and especially Macs, do ... :) (I'm specifically thinking of 32-bit addressing being turned off, when the About This Macintosh will show all the memory, but the system will seem to be using almost all of it, and there's no indication about how to get it to stop using almost all of it)
 

Aektann

Well-known member
I’ve preformed the “real work” check by booting my 4MB SE into System 7.5 and making all the remaining memory used by launching Excel. Yes, it worked flawlessly. I didn’t cut anything.
 

desertrout

Well-known member
I’ve preformed the “real work” check by booting my 4MB SE into System 7.5 and making all the remaining memory used by launching Excel. Yes, it worked flawlessly. I didn’t cut anything.
So strange. I'm tempted to test this on my SE.
 
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