HP DPS-800GP NO POWER CLICKING SOUND HELP!!!

[NConstantinou]

Dear all,

i have the above power supply with stb voltage 1v.
if i connect the small board there is a continious clicking but no output voltages.
i changed c232 on which i have 3v on main capacitors 330v.
i also change c501 and c910 but nothing. transistors look ok.

can someone help!!!!

Thanks

[kasfamily]

330 V is too low , it should be about 400 V

[NConstantinou]

I am trying to find 270μf 450v capacitors but I found at 420v instead. Would that be ok for testing

thanks

[NConstantinou]

on the bridge rectifier i get 240v dc and on capacitors 360v.. is that correct!!

[CapLeaker]

Probably not. 240VAC x 1.414 = ~340VDC. You should have closer to 400VDC on the main filter capacitor. If you aren’t getting closer to 400VDC, means you PFC isn’t working. Make sure the PFC works first.

[NConstantinou]

i do have 460v now but does not power on.Disoldering on the board is very difficult. solder does not remove easily even if you apply flux.

[kasfamily]

Something is not real. Show high-quality photos of the board