Power supplies atx computer desktops Model: H250AD-00, 5v power supply failure (green wire), STW9NK95Z mosfet front-end power supply and main STB23NM50N power lamp (other common circuits have two power lights The rectifier circuit is still working well, removing the STW9NK95Z from the circuit at G 0v pin, D 450v pin, S 0v pin, these two mosfets are still good but still no 5v green wire. How to check two ICs TNY274-280 and FAN4800A live or die ? File sharing and storage made simple
Confused here too.
I know nothing of the DELL unit, but ATX green wire (pin 14 on 20 way plug or 16 on 24 way) is the PSU 'ON' when you link it to ground pin 5 (common). Not a supply wire.
I know nothing of the DELL unit, but ATX green wire (pin 14 on 20 way plug or 16 on 24 way) is the PSU 'ON' when you link it to ground pin 5 (common). Not a supply wire.
Green wire is input, not 5v output. When connected to ground (green to black) power supply starts, otherwise off.
Many atx ps also require some load on 12v and 5v to start on bench. E.g. 12v lamps.
Atx ps often die because of electrolytics caps going bad. Check all caps on all the outputs visually. Bad ones often show bulge (deformation on top). Replace with low esr types 105 oC .
So far I know Dell did not make ps by themself, they bought from various vendors.
Check here for similar circuit diagram as yours, look for same controller ic ...
AT and ATX PC computer supplies schematics
Many atx ps also require some load on 12v and 5v to start on bench. E.g. 12v lamps.
Atx ps often die because of electrolytics caps going bad. Check all caps on all the outputs visually. Bad ones often show bulge (deformation on top). Replace with low esr types 105 oC .
So far I know Dell did not make ps by themself, they bought from various vendors.
Check here for similar circuit diagram as yours, look for same controller ic ...
AT and ATX PC computer supplies schematics
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