I would take
everything out, memory, drives etc., use a known
good apple brand mouse and keyboard and see if some minimum
system doesn't get some kind of response. ADB, SCSI, and
memory can all look like this IIRC.
I thought the fx required memory to be present to boot? So far my minimal
system has been system ROM/memory/known good kb/rodent but I still don't get
+5V on the ADB cable to the keyboard or anywhere on the motherboard
connector.....it's looking very dead-PSU-ish now.
BTW now is when its nice to have a good old
Snooper board around. ;)
I assume that's a diagnostic board for dead nubus machines?
Yeah, Snooper has a nubus card that checks all voltages etc. with leds.
Does the ADB have a fuse?
Heh, about time to try swapping in a known good IIfx motherboard. ;)