Bad power supply?

hi,

ATX-300-12Z Rev.BD is a 24 pin ATX with SATA

to initially check if it is good you can try these for a test:

1) disconnect the AC mains plug from the wall outlet

2) disconnect the 24 pins to the main board

3) try to have a small piece of wire short the green and black wire

through the hole on the connnectors

4) now try to just momentary plug the power supply to an outlet

i repeat momentary

5) if the fans of the power supply spins, it means your power

supply is initially good.

6) these part should be done with a lot of care measuring

output voltages.

7) try to wear rubber shoes and not to touch any metal connecting

to the unit.

8) there are a lot of other output voltages, initially that is only 12v

as it is the supply of the fan.

9) there are, 3.3V, 5V stndby, 5V running , there are also negative

voltages

10) to be very precise with the measurement digital tester is best

if you dont have these even the analog ones are good.

11) please dont try to measure voltages if you feel you cant measure

the output voltages have someone assist you and note down

the voltages you have taken.

12) please be careful when measuring output voltages

your reference is the black wire, should be connected

to the negative probe of the multimeter.


hope i have helped you, thanks for using Fixya!

Do yo have a volt meter or an atx psu tester?
you can check voltage to see

If a power supply is bad, your pc will turn off or/and turn on and turn off. As long as your system is running without and shut downs your good.

However if your pc is turing off, I would change it as soon as you can. basically what is happening, when you unplug everything there isn't much of a draw on power so the light remains steady, but when you plug devices in there is a draw and the PSU cannot deliver.

I hope this helps.