Zydec Superboard 1.5MB RAM mod...

[mrbombermillzy]

Ok, I have a Zydec Superboard, otherwise known as the AMRAM1M5 Issue 2. It is a trapdoor card and has 1.5MB onboard 'Slow' RAM with an on/off switch and a Gary adapter to allow the extra 1Mb RAM.

Now, I have a Rev.5 A500 board, which when doing the JP2/JP7 area track cut mod and the change to the 8372A Fat Agnus SHOULD give me 1MB of Chip RAM. However, because there is the extra RAM on the board, will this extra 'overflow' out into Slow/Fast RAM mapped area, will it be unrecognised, or will it, worst case, not let the Amiga boot?

Had a trawl around the Amiga forums, but havent found someone with this combo doing the ChipRAM mod.

[terriblefire]

Im not sure what will happen. The extra should appear as slow ram but i cant picture in my head what that mod actually does.

[mrbombermillzy]

Well, heres the trace that needs cutting and jumper pads JP2 that need changing for the Rev.5 board:

Capture.PNG

I would just suck it and see, but if it doesnt go well, I dont want to have to restore a broken track if I can help it.

[krs]

I just installed this 2MB trapdoor expansion the other day in my Rev 6 board, and did the chipram mod. And indeed I now have 1MB chip ram and 1.5 MB slow ram. So I'd guess it'll be the same with yours.

As for restoring the trace, it's just a matter of removing the jumped pads with some solder wick and then connecting the other two together again. So a very easy restauration should it be necessary.

Edit: Oops I didn't see this was such an old thread! :o
Well maybe the info will be helpful to someone.