[Info-vax] rx2620 power supplies / VRM voltage low

[George Cornelius]

In article <a9a05da3-87ee-44b0-9084-1109d542ea06 at googlegroups.com>,
 Steven Schweda <sms.antinode at gmail.com> writes:
> Has anyone considered the possibility that the VRMs "on
> the motherboard" are bad, and not every main power supply in
> the world?  I know nothing, but I can imagine a case where a
> fresh power supply might be just barely able to overcome a
> faulty VRM, but not for long.  Swapping main power supplies
> may be much easier/cheaper than swapping VRMs, but how many
> bad main power supplies do you think are out there?
> 
>    How much would a whole spare system cost?

OK, well, thanks to the group.

The answer to my question: this is anomalous.

If this person has been getting supplies from people who
are not being up front with him, then that's the first
problem.  The second is that he is asking people who are
not equipped to solve his problem to do his troubleshooting.

Yes, I have component level repair experience, but that
was a million years ago.  I don't think I have ever taken
a soldering iron to a motherboard except once in the old
days when a soldered-in rechargeable CMOS battery failed,
I suppose a NiCad.  So I probably won't be trying my hand
at such things today.

We do have a number of techs who could check the
capacitors and attach meters to test points.  That
will likely not happen either except maybe to convince
the "approved" vendor who sent us the first failing
replacement that he needs to be considered for removal
from approved status.

By the way, it is apparently well known that there
was an era not so long ago when there were large
numbers of faulty electrolytics from China and
Taiwan making their way into PC's and servers,
ultimately resulting in recalls.  Certain
manufacturers were affected more than others,
HP being perhaps one of those less affected.
I do have sitting in the hall an HP PC, one that
was shipped as a console for a GS1280, I am told,
that has video display issues along with bulging
capacitors on the motherboard.

I am going to discount that, though, and just
say that electrolytics are known to have finite
lifetimes and there are people who will just
turn around used parts with minimal effort
invested; and those who don't understand that
deserve what they get.

We are perfectly capable of buying a working
system and moving everything over to it, but
I wanted to make sure that there was not, say,
a known issue with power supplies in certain
classes of servers first.

So thank you all very much for your help.

George Cornelius