Hi pSyChO dAd
First of all, I see that you have a jumper connected to ST2. ST2 is for connecting the memory board to the Gary adapter. Jumpers are used in JX A & B.
Anyway, I have Gigatron MiniMax in one of my A500. I didn't get any memory out of it without the cable connected to the Gary adapter. I took a picture of my setup and marked the pins if you want to make your own cable (I used my own pin numbering). Just connect 1 to 1, etc.
Also you might get 512KB if you remove the Gary adapter and set jumpers to JX A and B as the manual suggests. I have not tried that myself.
Hope this helps
