This is a dumb question, but one I'd been meaning to ask for a while.  What would happen if you use one of these devices (or a ZorRam) on a Zorro II system?  Would they be able to use 8MB of it?  Or not see it at all?

Reason is pretty logical, if I wanted to replace old full-size ZII RAM expansion boards with more modern components, better reliability, better airflow inside case, etc.

Answer #1, yes I've used a ZorRAM and a BigRam+ in A4000T & D's (even an A3000D) and they work fine.  When used with a Mediator (which can grab 512 MB of Z3 address space) one has to be careful with the way the Z3 address space (1 GB) is allocated; if you do it incorrectly you will run out of address space.  For example, the ZorRAM 128MB allocates 256 MB of space thus wasting 128 MB of address space.  The two ram boards are otherwise identical except for the layout: the BigRam+ has all its RAM on 1 side, and only comes in 256 MB (the amount it allocates).  Otherwise the parts and firmware are the same.

Answer #2,  Sorry 442 or is it 455? Both are Z3 (32-bit boards) and lay outside the Z2 24-bit address space; so a A2000 can't see it.

Yeah, that is why 32-bit RAM had to be put on the accelerator board itself when used in an A2000 (but boy, those 040's and 060's would make an A2000 fly)...

BigRAM+ is NOT guarantied to work in a A4000 with third-party BusBoards! Because of bad Z3 - termination! It is only guarantied in original Commdore Busboards or Tower-Models!

You don't say!

So BigRam wont work with a Mediator 4000 or in most cases it will?
ZorRam says it does work with the Mediator however AmigaKit does not have any available for sale right now.

i use a zoram 256Mb with the mediator and cyberstorm ppc. it works just fine. I have installed: radeon 9250,sb128,deneb usb.

I'm sure those who write aggressively with excessive punctuation will follow up this post with specific examples of boards that don't work well due to "poor Z3 slot Termination." Although the only A4000D towered model I had in the past, did work with a BigRam+.

I was in the Beta-Test Team of the BigRam+ and it was not working with Micronic and Eagle Crap in A4000 in stable conditions ...... Mediator could work, but NOT guarantied... I never said it is not working....

BTW: if you loose a TCP-Packet, who cares.... if you loose Bytes in RAM ? Do what ever you want.....

I just installed a BigRAM+ board in my A4000 but ran into a problem. I have WB35 on my hard drive. It does not see the board at all. But if I boot off a WB31 floppy, it works just fine. Any ideas?

When you say "It does not see the board at all", what tools are you using to detect it?  See if it shows up in Scout or SysInfo or ShowConfig or similar?