I recently saw mention of a Mac IIsi memory hack project and that got me thinking of possible upgrades for my IIsi.
When I first picked it up about two years ago I installed an FPU and upgraded the video card to a Supermac Spectrum 24 PDQ+ 24 Bit.
The RAM is only at 16MB so I could definitely upgrade that. To be honest, I am hoping to find something a bit more exotic. The Radius Rocket was suggested earlier - I'll be keeping my eye out for that.
One thing I'd seriously consider, especially if you're entertaining the idea of using a Rocket, is upgrading the power supply. A lot of the more highly desired NuBus cards (video cards, Rockets, etc) tend to suck quite a bit of power, and the IIsi has always had a reputation for having a very weak PSU.
With respect to the RAM, you can use 16MB SIMMs in the machine. I once took a IIsi up to 65MB (I have 17MB in my current one, like the OP - add the 1MB on the board to get the total memory), dropped a 250MB hard drive into it, then proceeded to install Mac OS 8.1 on it. Used the BornAgain patch to add the necessary '030 code. It worked, but did feel more like a Mac Plus than a IIsi.
Thanks. Any suggestions on where to source a PSU upgrade? I assumed the modular design would mean the list of PSU alternatives pretty short.
I'll third that motion for proper provision for the power and cooling budget of a Rocketized IIsi.
The PSU in my original IIsi blew and I've been using a Q700 PSU mounted precariously upon the empty shell of the Magic Smoke dispenser. Now that the Rocket/IIsi combo is finally fully operational, I've run it a few times with the case closed, using a stock PSU without problem so far.
However, I haven't run it for very long at all on any occasion while in that configuration, so the Magic Smoke hasn't really ever had time to build up enough pressure to overcome its containment field.
Once I've completed the sub-basement PDS card installations, I won't dare attempt to fire it up with a stock IIsi PSU. I think the plans for an ATX refit of the original PSU enclosure are over at the barracks as well.
I'll have to check it out, I haven't been active much over there lately. Though I have been checking in to see what's going on and to see if anyone could use my help.
Right now I'm anxiously awaiting the arrival of a very interesting SIM Expander for my IIsi memory hack:
That's going to be a lot of fun to pick apart!
In the meantime, why don't you check out uniserver's 4MB on the MoBo hack. That would be a great initial project for your IIsi.