A25000 RAM card in an A2000

[richo132]

I have an A25000 RAM card that I want to use in an A2000.
Computer has a 3.1 ROM plus A2091 SCSI card with 2Mb RAM.

I'd appreciate some help with a couple of issues:
1. What is the function of jumpers J1 & J2 on the A25000 ?
2. I want to load WB 3.1 on the A2000
   HD setup functions only work correctly with base M/B RAM
   ie if I remove the A25000 and disable the A2091RAM.
   Any suggestions about the cause of this ?

Thanks.

[richo132]

Thanks for taking the trouble to put together such a detailed response. I hadn't noticed J3 - well the pads for it anyway. This is definitely worth knowing about. Having read the article about VBAK2091, I'm wondering if it would make much difference to an A2000 - it seems mostly to be pitched at A4000+A2091. Do you have any experience with this ? Cheers.
(PS my A2091 has V7 ROMs)