The A2630 can be configured for 2 or 4 meg of RAM. So I would check the jumper setting to make sure it's not trying to grab 4 meg of Zorro2 space.
I seem to remember having a similar problem many years ago. I would definetly check the jumpers to make sure the two boards are not competing for the same address space. I'd take a look at how the jumpers in my A2000 are configured, but sadly I'm half a world away from my Amiga at the moment. Good luck!
