Different boot problem...
Thaddeus P. Floryan
thad at btr.BTR.COM
Fri Mar 1 22:12:56 AEST 1991
In article <12880 at helios.TAMU.EDU> n138ct at tamuts.tamu.edu (Brent Burton) writes:
>[...]
>The voltages were the same as I mentioned in my last posting.
>EXCEPT the -12V (pin 18 on the PS-->MB cable) was +0.79V. This is
>a bad sign. What hints are there?
Sounds like a bad -12V IC regulator. As I recall, the -12V regulator is
right at the front of the power supply, so replacing it should be
straightforward.
Not too much on the system uses -12VDC, and I don't believe anything could
have been damaged by the voltage you measured, but what concerns me is what
caused the IC regulator to go belly-up. If it's a problem with other
circuitry in your system, then you gotta problem. Maybe temporarily using
an external power supply may help isolate the trouble area if there is a
problem on the motherboard.
If you need the power supply pinouts (part of one of my regular postings in
this regards), send email.
Thad Floryan [ thad at btr.com (OR) {decwrl, mips, fernwood}!btr!thad ]
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