It's basically the same board as here https://www.badcaps.net/forum/showth...ghlight=1970NX just the D108 is present with cap C121. PSU is clicking as in protection mode, no idea why.
There is supposed to be +5 and +12 V and that extra rail with an N-FET (AO4405) which outputs to some sound bar (not sure if the owner used it). It is somewhat darkened around the source but FET does not seem to be shorted (I read the internal diode so worst case is the FET is opened). Small SOT-23 transistor (most likely 2N7002) the same.
When I turned it on I read voltage oscilating around as much as 20 V on the +12 V rail while +5 V was done around 1,5. I thought maybe the FETs are bad anyway and the voltage is from the auxiliary rail but when I lifted the D108, voltage dropped to 18 V on +12 V otherwise the same.
All rectifiers and inverter FETs read OK as well as SMD diodes near LD75521S controller.
There is supposed to be +5 and +12 V and that extra rail with an N-FET (AO4405) which outputs to some sound bar (not sure if the owner used it). It is somewhat darkened around the source but FET does not seem to be shorted (I read the internal diode so worst case is the FET is opened). Small SOT-23 transistor (most likely 2N7002) the same.
When I turned it on I read voltage oscilating around as much as 20 V on the +12 V rail while +5 V was done around 1,5. I thought maybe the FETs are bad anyway and the voltage is from the auxiliary rail but when I lifted the D108, voltage dropped to 18 V on +12 V otherwise the same.
All rectifiers and inverter FETs read OK as well as SMD diodes near LD75521S controller.
Half of the computer problems is caused by bad contacts 
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