Destroyed A2000 motherboard?

[orb85750]

OK, based on my symptoms, I think my A2000 motherboard is shot due to my previous stupid tinkering and testing.  Do you agree?..................

With new power supply, no 030 card, no SCSI card, I get a black screen and floppy is not even recognized. (Everything is plugged in properly so far as I can tell!)  No difference if I add the 030 accelerator card (no surprise there).  If I add the SCSI card (which has the hard drive containing the OS that is supposed to boot up), the computer won't even turn on.  My question:  Could it be something other than the motherboard, given the above symptoms?

Thanks, -Dave

[trekiej]

What configuration did you have originally?
Do you have the old power supply?
Did it work with the old power supply?

[orb85750]

trekiej wrote:
What configuration did you have originally?
Do you have the old power supply?
Did it work with the old power supply?

The old and new power supplies both produce the same results.  Yes, I have both.  Original configuration was with 030 accelerator, SCSI interface, and memory board.  Everything was OK, until I improperly attached a Vlab Motion board to the SCSI chain (it did not work properly when in the Zorro slot only).  Turns out that the 50-pin connector on that board is for some other optional accessory, not SCSI chain!  (No hardware manual in hand, obviously)  Thanks, -Dave

[orb85750]

Other evidence I should mention:

Zorro slot voltages: Appear to check out fine!
Floppy power? YES
Hard drive power? YES (my 2nd drive, not mounted on SCSI board)
LED power indicators? YES

....but nothing kicks in when I power up, so I have the black screen (worse than "blue screen" in Windows).