What is the Maximum RAM on a Mac II Series Mac?

[Sherry Haibara]

Speaking of memory, I've been pondering just how much memory should I put in a recently acquired Macintosh IIsi (it currently has 3MB, which is really unacceptable). 

My basic goal is to run System 7.5.5 or Mac OS 7.6.1 at an acceptable speed, and maybe play some games on it (nothing really serious). I've been thinking of running A/UX on this baby, but I guess I'd need to find a coprocessor PDS board before (any suggestion?). 
I googled a bit and I was oriented towards putting 16MB on it, would it be enough? Should I look directly for a more substantial 64MB upgrade?

 

[Elfen]

For that IIsi, I have seen many networking cards come with a with an empty socket for an FPU. 

For memory, max out what you can afford. I think somebody was selling some ram here or $30. But in the very least one might want to over clock the cpu to 25MHz. If you want AUX for it, it will need the RAM and Hard drive as much as possible.