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blisca[_2_] blisca[_2_] is offline
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Default Motherboards Polyphase buck converter.Who start it?


Hi ,
please,forgive the form of my English

i have to repair an industrial motherboard, model ITOX G4S300,
it is necessary to make a machine working,capacitors were already changed
in recent past.
Disks diconnectd,CPU and memory replaced,tried with onboard and AGP video
card,no video outputs,beeps neither
,the only sign of working are spinning fans .
+12V,+5V and +3V are present on ATX connector
The most noticeable thing is the lack of any PWM activity on the gates of
each of 6 MOSFETS forming the buck converter, commonly placed close to the
CPU.
The question is:
is this dependent only by the PWM controller itself or something wrong
from the BIOS (that of course i can't check) or from other hardware could
stop the buck converter from working?
In other words,the PWM should run in any condition or not?

Many thanks for your help and your time spent reading this

Diego
Milan,Italy

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