Well, I finally decided to try my IIfx ROM SIMM in the IIsi despite the lack of confirmationthat it has been done successfully or unsuccessfully already, without damage to the IIfx ROM SIMM or the IIsi.

I got no boot chimes from the IIsi, but the IIfx booted just fine after that little experiment!

Phew! NO OOPSIE! [] ]'> [)] ]'>

edit: I finally remembered where I'd seen the reason that this won't work . . .

. . . AFTER I did the experiment! :

From the Another IIci ROM hack thread:

But until then, is anybody interested in boards? I'd be happy to send out bare boards to anyone for $2.90 (1/12 of my PCB order cost) plus the cost of shipping Like I said, the SIMM should work in any of the II series Macs that have a ROM SIMM socket with the exception of the IIsi but that can be fixed by cutting a trace, and also the SE/30.

Click to expand...

Food for thought! HRMMMMMM . . . }