@marcfrick:
one of the worst weekend in my entire life: for some reasons I had opened my A4000T (maybe I was adding a SCSI terminator) and noticed that the coin battery was not soldered but in a battery-holder (sorry I don't know the right term)...since it was discharged I tried to remove it...but doing so the battery-holder detached form the board. Even though I did not need it (I was using external batteries) I decided to repair it. So I dismounted everything took the motherboard to a nearby electronics shop and in few minutes they resoldered in place the holder. I returned home, re-assembled the Amiga and... blank screen. No sign of life. I felt completely lost.
My dream machine dead. For 2 days I tried and checked the cpu board connectors, video module and disk module connections, SCSI connectors, changed cpu boards, simms...
then I saw it... it was one of the 50 pin ribbon cables connecting the motherboard with the small board which terminates the SCSI bus. I reconncted it leaving the leftmost pins unconnected (so any pin was in a wrong hole).
It was hard to see, inside the case. Corrected and the Amiga came back, alive n' kickin'.
So my advice is to recheck connections of the disk module, if they're wrong prevent the entire system from booting. In my case the wrong connection didn't do damages, hopefully this your case too.
I told you my story to restore your hope!
good luck!
