Hello.
Amiga 500 rev. 6A 1 MB chipRAM + 0,5 or 1 MB fastRAM (trapdoor slot) possible? How?
I expanded an Amiga 500 rev. 6A 0,5 MB motherboard to 1 MB chipRAM with 8375 318069-16 Agnus (PAL system, max. 1 MB chipRAM). Original Agnus 8371 (max. 0,5 MB chipRAM).
http://s2.postimg.org/8o0x83w69/A500_6a_1_MBCHIP.png
My motherboard: http://amiga.resource.cx/photos/photos/a500rev6a-2.jpg
That is a good question. I don't know the answer. It would be interesting to put an A501 or clone on your system to find out. One problem would be is this "fast" ram would be slow. As far a address space I think up to 1.8 megs of slow ram is "possible" on an amiga but would require some level of hacking or gary jumpering.
further I agree with Greyspirit true fast ram will be faster than trapdoor slow ram.
Or get an edge connector ram card of some sort with true "fast" ram.