13 Dec
2006
13 Dec
'06
2:28 p.m.
On 12/13/06, Tim Shoppa <tshoppa at wmata.com> wrote:
Thank you, but it is different. It makes a continuous sound that is more
like a static discharge. The computer still works, so it might not the power
load problem. Furthermore, After about 6 hours of use, the sound of the
power supply seemed gone.
This is the symptom if there isn't the required minimum power load
It is on the CPU side. It sounds like there is a
high voltage leakage
problem.
You turn it on, and it goes "squeak squeak squeak squeak"? Maybe
the LED on the supply is faintly blinking at the same rate? in the Q-bus backplane. The power supply begins to
start up, doesn't
see enough load, and shuts down, and this repeats every second
or so.
For minimally configured systems there was a Q-bus card with
a bunch of resistors to suck up some current.
I think in the box, that one of the two power supplies does the
odd-numbered slots, and the other does the even numbered slots.
Loads must be distributed to cover both supplies and both supplies
need their minimum load met.
I did not know this. I thought they worked for each half of the QBUS. I have
a M9060 that I put in the very last slot to make the left side power supply
happy. Maybe it happens to be an even numbered slot.
vax, 9000
Sometimes even if you have the required minimum load the power
supply will not start up with this symptom. Adding
more load
seems to help!
Tim.