AT&T PC 6300 Plus Unix box

From: Russ Blakeman <rhblake_at_bigfoot.com>
Date: Thu Sep 30 01:40:06 1999

Looks more like a different machine as the 6300 PC is an 8086 processor.
This one shows an i286 and I have a feeling it's a wide based AT sized
case with a dark brown band around the outside almost like a bumper.

Bill Yakowenko wrote:

> Hey all,
>
> Yesterday I scooped an AT&T PC 6300 Unix machine on its way
> to the dumpster. Got it home, powered it up, and now I know
> why. It displays "Parity error on system board" and locks
> up. Actually, it displayed a bit more:
>
> Resident Diagnostics
> Ver 2.05P
>
> CPU (i286) PASS
> ROM Module PASS
> DMA Timer PASS
> DMA Control PASS
> Interrupts PASS
> Parity error on system board
>
> It seems to have 1MB of RAM, half socketed (36 81256's).
> So I yanked the socketed chips, and tried again. Then
> it did almost the same thing, but displayed a running
> count up to 512K before that parity message.
>
> So, what's next? I'm guessing that at least one of the
> socketed chips was bad, because it got farther before
> barfing when they were removed. But there is some other
> problem too, maybe in the soldered-in RAM chips, or
> maybe in the parity-check circuit itself.
>
> Anybody got a service manual or schematics or a big pile
> of clues for this thing?
>
> Cheers,
> Bill.
Received on Thu Sep 30 1999 - 01:40:06 BST