On Fri, 14 Jul 2000, Nathan Raymond wrote:

> >I wanted to try this since then, but could not find ROM-SIMM
> >model IIsi.  It appears to be vary rare.

Yes. I had/have one. I bought my IIsi on October 16, 1990. That was the
day after it was released, and a Tuesday. Thursday of that week it died,
and I got it into the repair place (on Friday) before the repair dude knew
it was out. Repair consisted of a mother board swap (the video memory
died). When swapping everything over, the repair dude swapped the ROM SIMM
over too, even though the new machine had on-board ROMs.

> Speaking of ROM SIMMs, does anyone have the definitive reason why 
> Apple did things so differently with regards to their ROMs?  Some 
> machines have the ROM soldered with no slot, some have it soldered 
> with a slot and a jumper to select slot or soldered, some have no 
> jumper but a slot and soldered, and some have just the slot with a 
> ROM SIMM in place. 

One of the reasons I've heard about for the IIsi was that the ROMs were
not finalized at the date of the initial production run finalization, so
the very first ones depended on the ROM SIMM (which evidently could be
made closer to the release date).

Take care,

Bill