PB Duo 210 - blank screen after chime, but interrupt works

I have a Duo 210 that I'm trying to get working.

It currently hangs at a gray screen (not a white screen) at boot, and will not progress to boot. The machine does chime. If I hit the interrupt key combo (cmd-Pwr), I do get a Sad Mac on the screen (0000000f 0000000d).

I've already recapped the machine.

I also did note that there's no +5V at the hard disk connector. I believe that's controlled by the PG&E but I couldn't tone my way from the MOSFET driving it back to that chip.

Does anyone have any ideas on what I can check next? Does it need a functioning PRAM battery to boot? I saw mention that the 2300 would not even power on without one, but that's different to what I'm seeing.

tattar8 said:

Does it need a functioning PRAM battery to boot? I saw mention that the 2300 would not even power on without one, but that's different to what I'm seeing.

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Can't help with your main issue, but they do not need a working PRAM battery to boot. I believe some/all of the Duos will only boot with one of the two power buttons if the PRAM is dead, but since you are getting power that isn't your problem.

Possible a dead scsi chip. If the scsi craps the bed in these it usually fries the scsi chip. Had it happen on a duo 230 twice.

Well that would be unfortunate. I'm guessing the boot ROM is waiting for a response that isn't coming. I could scope some of the output pins for signs of life.

Any idea where to find a replacement? eBay only has a listing for the -8JC variant, which I'm guessing would be too slow.