Which Macs can use 8 MB 30-pin SIMMS?

[JRL]

I read from a thread that not a lot of Macintosh computers with 30-pin SIMM slots support 8 MB SIMMS. What Macintosh models support these SIMMS?

 

[equill]

Officially, none. Even one of the most catholic Macs (in terms of its taste in RAM), the IIci, uses 256kB, 512kB, 1MB, 2MB, 4MB and 16MB. If your mileage varies, offer thanks to the deity of your choice. Your best hope is probably in the late four-slots-per-bank models (Q900/950), and only a distant mebbe in the Q700.

de

 

[tmtomh]

I've never even seen or heard of 8MB 30-pin SIMMs (though I've got a box full of 8MB 72-pin SIMMs in the basement - as I'm sure many of us do!)

M

 

[equill]

They do, and hence the interest by JRL, presumably. The real 'clincher' of their existence is Apple's taking the trouble to record (Apple Memory Guide, 2001 and earlier) that it had not tested them, and therefore did not support them.

de

 

[Charlieman]

Over the years, I know that I have picked up the strange 2MB SIMMs and would not be surprised to encounter 8MB SIMMs in the "untested 30 pin SIMM" box.

I'm interested in how 2MB and 8MB SIMMs work in SIMM doubler devices, and how they are recognised in Macs that don't use that size.

 

[equill]

2MB SIMMs also work in the Classic II. Our first (joint) Mac arrived with 6MB (2MB on the MLB), but was later upgraded to 10MB with 2 x 4MB SIMMs in place of the 2 x 2MB. But 10MB is the ceiling for the Classic II, which also needs paired cards.

de

 

[trag]

IIRC, the 8 MB SIMMs definitely work in the IIsi. I bet they work in the IICI as well. I remember reading a Mac User or Mac World or both article(s) back when the LC, IIsi and something compact came out together and a big deal was made of the IIsi using 2 MB and 8 MB SIMMs.

Or that is all a big hallucination, but that's the memory I have.

 

[gobabushka]

if they work in the iisi, maybe they work in an se/30?

 

[equill]

Especially if the SE/30 has a IIsi ROM card? There is, however, still a generational gap between the SE/30 and the Mac II machines. And if the scarcity of IIsi ROMs were not enough, there is the further consideration that 8MB 30-pin SIMMs are considerably scarcer than 16MB SIMMs.

de

 

[zuiko21]

This is an old thread, but I'd like to add some data...

8 MiB SIMMs do work on the IIsi, but not on the SE/30 -- Death Chimes. They seem to be recognized OK by the Quadra 700; but mine are physically too large and thick (chips on both sides!) so they keep pressing against each other on the Quadra's "slender" sockets, preventing a reliable contact -- once it managed to boot all the way with them, but testing that configuration made me hear the Death Chimes for the first time ever...

2 MiB SIMMs don't work on the SE/30 either. However, I think the memory controller chip has something to do, because the IIx (same ROM as the SE/30) is able to boot with the very same SIMMs, although only sees 1 MiB out of the two

The Quadra 700 works fine on 2 MiB SIMMs, as does the Colour Classic; but on it they were a tight fit, because of the PAL chip on them -- they have only 4 DRAM chips each.