Strange IIsi Issues

[Stephen]

I have two IIsi machines, when I use a BMoW ROMinator II I get instant death chimes on both machines. I also get instant death chimes when I use a Kero's Mac Mods ROM SIM loaded with System 7.1.0.

1. I can boot both machines into System 7.1 using a BlueSCSI, no optional RAM or ROM SIM.
2. I can boot one machine into System 7.5 with 4 sticks of 16MB RAM, no optional ROM SIM.
3. The other machine instantly death chimes with even a single stick of RAM.

Any suggestions? I find it peculiar that both machines instantly death chime with the ROMinator II installed.

 

[robin-fo]

Some people had issues with modern SIMMs due to bad contact (PCB too thin). Try gently pressing the SIMM against the socket.