SE/30 Unstable behaviour after 128MB RAM install

[lagomorphonic]

After chugging by and barely being able to get along with the 5MB RAM my SE/30 had in it, I finally got myself 128MB. Unfortunately, after the install, the computer behaves erratically. In particular, certain programs (Emacs especially) now take a ridiculously long time to load, when they don't flat out freeze the machine. Apart from the long load times, the machine will often just freeze randomly and not recover, which is the real problem. I'm running System 7.1.1 with the BMOW ROM-inator II and also an 8GB SCSI2SD (512MB OS partition and two 2GB partitions). 32 bit is enabled and Virtual memory is disabled. The disk cache is set for the "default" of 4096k, (was originally set to 32k, no difference in behaviour between the two) Apart from being a bit slow, I'd never had any issues with the machine or freezing before the RAM upgrade.

Are there any other "obvious" things I need to do to the machine to get the 128MB working properly?  Maybe I've got some bad RAM? Since the ROM-inator disables the check, is there another way to do a check? Any help would be appreciated. This is very frustrating as I've finally gotten the machine into a nice working state that I could be quite productive on (mainly using Emacs/Textures for documents) and the performance boost from the RAM upgrade would have been great. Now the machine is essentially unuseable. Any help would be much appreciated! Thanks.

 

[tanaquil]

I hope you can get good advice - I'm not sure what to suggest. I assume you've done obvious stuff like re-seat the RAM? 

I just got my SE/30 back into working order and was wondering where you got your 128 MB - I have 69 MB now but 128 MB would be satisfying. (Because I need 128 MB to play Crystal Quest?)

I will be following this thread to see what you learn. Good luck!

 

[trag]

I would get a voltmeter and monitor the 5V line while the machine is running.   At a guess, your power supply is alaready marginal and adding the memory is loading it enough to drag the voltage below where the logic can operate.

Alternatively, it could be a rotted trace or some such on one of the high address lines to RAM which don't get used with smaller capacity SIMMs.

Try installing 64 MB and see if the problem persists.  If it goes away, it's probably the power supply thing.   If it persists, you still don't know, because 64 MB could be enough to push it over the edge.

 

[lagomorphonic]

Thanks for the replies. I did reseat the RAM but no luck. Trag that was what I was going to try next: using only 64MB "just to see if that helps". I'll try the voltmeter, though if it's not up to voltage there's not much I can do about it right now. Nothing on this one has been refurbished and I'm waiting on my recapped board to be sent to me which will be awhile yet (though that still doesn't address the power supply).

Tanaquil I ordered it from macsales.com aka "other world computing". It's brand new RAM.

 

[tanaquil]

Glad to hear OWC still has it! For some reason I thought they stopped carrying it. 

 

[lagomorphonic]

The good news is that I took out the RAM from block B leaving only 64MB and ran the machine for quite awhile last night without any freezes. The programs that took a long time to launch before with 128MB were quicker this time and seemed to launch more stable-y. However I noticed that the display was sort of flickering a bit more than usual which I guess would be consistent with what trag said about voltage? Tonight I'm going to try to swap out these four SIMMs for the four I pulled to see if maybe there was something wrong with one of those other four... I'll measuring the 5v line at some point this week when I have a little more time to dig out my multimeter.

 

[dochilli]

Did you recap the analog board? Old capacitors can cause flickering of the screen. If you measure the 5 and 12 V, they must be constant for some minutes.

 

[SE30_Neal]

I just brought 128mb from owc for my se/30 but not managed to get it working yet or the rominator ii I brought, grey fuzzy lines and funny sound :/  thought I would have to install the  rominator first as I believe you need to res edit some stuff if you are using above mac os7.1. Thats a point actually lago did you do the res edit thing with your rominator? Neal. Really like to know as I’ve not been to successful upgrading mine either.

 

[jamesmilne]

Hi SE30_Neal,

I bought 4x16MB SIMMs from OWC. When I tried them on their own, they didn't work, same symptoms as you. Corrupt screen at boot and sad mac sound.

I tried them in the first 4 slots with a further 16MB (4x4MB SIMMs) in the remaining slots, but that didn't work either.

What worked for me is 4 x 4MB in the first 4 slots, then 4 x 16MB in the remaining slots. I'm currently rocking 80MB of RAM, which is not too shabby. I believe this goes against what I had read about putting the larger SIMMs in the first slots, but who knows. I've had zero issues since the upgrade.

 

[SE30_Neal]

Thanks James. I will try again maybe this weekend if i get a chance too. I’m not a electronics person so not a 100% comfortable taking it apart etc.. don’t get me wrong i have built a few pc’s in my time but thats a few boards, thermal paste and some drivers. A 30 yr old macintosh with a crt is a bit different, i also managed the knock the screen adjustment last time so its now a bit wonky so i need to try again anyway. I would be happy with 80mb ram though 

neal

 

[lagomorphonic]

I just brought 128mb from owc for my se/30 but not managed to get it working yet or the rominator ii I brought, grey fuzzy lines and funny sound :/  thought I would have to install the  rominator first as I believe you need to res edit some stuff if you are using above mac os7.1. Thats a point actually lago did you do the res edit thing with your rominator? Neal. Really like to know as I’ve not been to successful upgrading mine either.

SE30_Neal if you don't use something like a rubber band or paper clips to apply forward pressure to the ROM-inator it will create the vertical stripes issue. Mine does this consistently as the rubber bands I use are not tight enough. For now, I'm just lightliy pressing the ROM-inator forward with my finger when I boot and that will fix the issue with the stripes. It's fine for now because I leave the case off of my SE/30 for now as I'm constantly going back and forth adding software via the SD card. No I have not done any Res Edit stuff nor have I seen any reference to having to do this. What is it?

Dochili no the board is not recapped nor is the logic board so it makes sense that there'll be an issue like this. Not much I can do about it in the meantime until I recap them.

On a side note, what can even be run on an SE/30 that would consume up to 128MB? I often wonder what the point is. I upgraded pretty much for the same reason everyone else probably does: because it's cheap and "because you can".

 

[trag]

Whether we realize it consciously or not, a lot of old computer collection behavior seems to be driven by, "I wanted that back in the day but I couldn't afford it, so I *really* wanted it.  Now I can afford it, so I'm gonna' buy it, darn it, even though it makes no rational sense any longer."

Hence, 128MB RAM in an SE/30 is a giant, "I couldn't afford that back in the day" acquisition.

 

[SE30_Neal]

no I hadn’t tried a paper clip or rubber band, will look into that

yes if you’re using os 7.5 or above you need to make a few tweaks via res edit https://www.bigmessowires.com/mac-se30-with-upgraded-rom/

lol yes i had 4 mb in my colour classic at college and really needed more for graphic design so yes completely agree with you now i have a few old macs for nostalgia i want them pimped so 128mb in the se/30 just because and I’m looking for a reasonably priced upgrade card 33mhz + would do it lol 

 

[olePigeon]

I ran into this exact issue when I was refurbishing SE/30s.  You have to have a 32-bit clean ROM installed to use 128MBs of RAM in a 32-bit "dirty" Macintosh, I couldn't find any way around it.  Otherwise I had to do the 4MB/64MB trick to get it to work with MODE32.

So I suspect once you get your ROM working, you'll be able to use your 128MBs of RAM.

 

[SE30_Neal]

Thanks ole, that was my plan rominator first as it was 32 bit clean and it also stops the memory check. I will try tomorrow after work  feeling a bit more positive abiut it now

 

[Bolle]

You have to have a 32-bit clean ROM installed to use 128MBs of RAM in a 32-bit "dirty" Macintosh, I couldn't find any way around it.

Interesting... I always was under the impression that MODE32 works no matter what memory configuration you have installed.

I thought my homebrew 16MB SIMMs sucked but I think I always tried the stock ROM when testing them in the SE/30. Might have to dig them out to test them again.

 

[SE30_Neal]

I had read somewhere they had to be 32 bit clean for the full 128mb but I’m far from knowledgeable on old macs and you can’t believe everything you read online but definitely read that whilst looking up about upgrading my se/30

 

[olePigeon]

Interesting... I always was under the impression that MODE32 works no matter what memory configuration you have installed.

I thought my homebrew 16MB SIMMs sucked but I think I always tried the stock ROM when testing them in the SE/30. Might have to dig them out to test them again.

@Bolle  Perhaps I should clarify that my experience was only with the SE/30 and its ROM.  Perhaps this issue is unique to the SE/30, but I don't know.  I haven't tried it on a Macintosh II or IIcx.  I believe that was the intention for MODE32, but it doesn't seem to work with a full 128MBs on a SE/30.  When I was refurbishing SE/30s I tried putting an SE/30 ROM into my IIci, and I was able to duplicate the problem.  So I can verify at least that it's an issue with the SE/30.

Putting a IIci ROM into an SE/30 made it work with a full 128MBs.

 

[trag]

Adding additional memory should not cause the machine to freeze/fail to boot under any circumstances unless there is something wrong with the RAM or the machine.

When RAM above the supported mark is installed in a 24 bit addressing Mac, it will still appear in the "About This Macintosh" screen, but everything above the supported mark will be allocated to the System.     So you'll see something like "128 MB installed.    7.5 MB free.   System  122.5 MB."

It could be that the SE/30 has different behavior from every other Macintosh, but I don't see how that's possible given the identical ROM/hardware between the various models.