17 Sep
2011
17 Sep
'11
10:03 a.m.
I've tried several things to no avail:
* I disabled onboard vga
* there's nothing in the PCI slots now
* I reseated the processor board
That would have been my next advice. I have found the position of the
processor board to be very critical at times.
* I unplugged the scsi bus and floppy cable
* I even went as far as removing all of the memory
and still there's no change: nothing from serial port 1, no beeps, no
OCP messages. The memory pull should have at least issued a set of
1-3-3 beeps, right? I verified and the speaker is working.
Yes. I would expect it to beep when there is no memory.
It seems that the B-Cache on the processor board can be prone to failure.
I've had this but I can't quite recall what the symptoms were. I will
check to see if I have any notes. The B-Cache can be disabled by
changing a jumper on the processor board and the machine will run without
it at reduced performance. The location of the jumper varies depending
on what processor you have.
I wasn't able to find able to find a voltage pinout for the power supply
to test it.
I think I took note of the voltages on the power supply connectors when I
was diagnosing a recent problem on mine. I will see if I can find my
notes.
(The power supply is uses significant amounts of power even when the machine
is switched off, so unplug when not in use.)
Regards,
Peter Coghlan.