• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

G3 Minitower questions memory and more...

Juror22

Well-known member
I purchased a G3 Minitower earlier this year and have been slowly upgrading items and repairing small issues e.g. I replaced the drive carrier, missing feet, etc. When I recently upgraded the memory, I purchased 2 modules of what was supposed to be the correct memory(256MB PC100 CL2 168 Pin SDRAM 2-2-2 Low Profile 16x8) and I was sent PC133 CL3 memory instead. After proving it would not work in my G3, they sent out the correct modules (they are correctly labeled as above), but when installed, My G3 only recognizes 128MB installed for each (Apple Profiler lists the slot and the amount 128MB).  Has anyone ever seen this issue with a G3 Minitower?  Is there any way to check the chips and determine if the memory is correct this time?  The motherboard is 820-0991-B and I am running OS 9.2.2 with the original 300MHz G3 (I have a 400MHz G4 that runs fine in it, but until I sort out the memory issue, I don't want to complicate the issue).

One additional question related to running the G4 chip (Its a MaxPowr ZIF upgrade)

The service source calls out for a gap filler, PN 922-3643, when a new processor is installed.  Any idea where I can get something like that?

It is not the usual paste-type material, but appears to be an almost asbestos-looking paper substance on the original processor, that the upgrade chip does not have.

 

Byrd

Well-known member
Hi Juror22,

You should be looking for double sided RAM - which I suspect your modules are not.  Certainly the profile of the RAM doesn't matter and I've used PC100/133 RAM without issue in beige G3s, but it takes some work to get all three modules running nicely.

Re: gap filler; if the original heatsink isn't a snug fit on the G4 CPU, this would be a thermal pad - available in various thicknesses you can cut to size.

 
Last edited by a moderator:

Juror22

Well-known member
this would be a thermal pad - available in various thicknesses you can cut to size.
I never knew this stuff existed!  All those times that I was SO careful with the foam ones in MacBooks, etc. because I didn't think there was a way to replace this stuff.  Thanks for the heads-up!  

The RAM is double-sided, here are a few pics... there are 16 total of these chips, front and back.

mem2.JPGmem1.JPG

 

Byrd

Well-known member
I never knew this stuff existed!  All those times that I was SO careful with the foam ones in MacBooks, etc. because I didn't think there was a way to replace this stuff.  Thanks for the heads-up!  

The RAM is double-sided, here are a few pics... there are 16 total of these chips, front and back.


Over time the thermal pad dries out and gets chalky, it can come off in little pieces and yes inexpensively replaced.

That RAM looks like it has Micron branded modules; for compatibility I'd look out for less generic modules - Hynix, Samsung, Hyundai, etc.

 

Juror22

Well-known member
Thanks for the advice.  On the plus side, it was cheap, but it came from a company that deals in Macs and has given me good items before, so I don't know what their deal is. 

 
Top