Sonnet Doubler Allegro for Mac II

[David Cook]

The SWIM does play absolutely no role at all at how much memory the Mac II will support.

The IIcx adds a GAL on the logicboard that is sitting between the DRAM control signals that the GLUE puts out towards the RAM to get around the "faulty" signaling sequence that sends higher capacity DRAM chips into test mode basically making them fail. The same is true for the SE/30.

Thank you for these answers. It really clears things up. I honestly couldn't see how the SWIM affected memory, but I have been reading that table wrong.

 

[Arbee]

Anyway, with this accelerator and the FDHD/IIx ROMs, you should be able to use any memory configuration that works for a IIx, IIcx, or SE/30.

 

[David Cook]

I was never able to find any SIMMs larger than 4MB. I don't think they exist.

Oh they do! I have a IIx with 128 MB in it.

 

[ObeyDaleks]

Oh they do! I have a IIx with 128 MB in it.

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Goodness (drool)! I wonder how much this would have cost back in the day.