Hacking GS memory card?

[RKFAIRCLOTH@unca.edu (Rhonda K. Faircloth)]

I've been poking around Apple's 1meg memory board for the //gs, trying
to increase it's memory capacity... hopefully to 4meg. Anybody have
any experience/knowledge in gs memory handling? I desolered the eight
dram chips already on the board and ran some wires to a socketed 256k
SIMM on a proto-board. This tested ok. I then tacked a wire to the
unused FRA9 (pin3) line, ran that through the same type of 
inverter/resistor (as the other address lines are handled) and
brought it to A9 of a 1meg simm. It would only give me 768k. 

Perhaps I shouldn't use FRA9? Perhaps I'm getting noise from my 
quickie-rigged protoboard wiring? I'm using a ROM3 GS. 

Anybody know of a PD/Shareware memory test program? I have Appleservice
diagnostic 3.0, which only recognizes certian "apple-made" configurations.