Turn on PSU w/o mobo

[laijosh]

So I need to turn on my power supply w/o the mobo. I saw some tutorials about how to turn it on by using a paper clip from the black wire to the green wire but I do not have a power switch on the back of my PSU =(. Any suggestions on what to do?

 

[delluser1]

You don't need a switch, hook up the jumper and then plug the power cord in.
Make sure to have a fan or 2 hooked up.

 

[jsc]

If you have a multimeter, you can check all the outputs. Yellow wires should be 12 volts, red 5 volts, orange 3.3 volts, blue wire -12 volts, purple wire is the 5 volt standby.

The gray wire is really important. It sends a control signal called something like "PowerOK" from the PSU to the motherboard. It should go from 0 volts to about 5 volts within a half second of pressing the case power switch. If you do not have this signal, your computer will not boot. The tolerances should be +/- 5%. If not, the PSU is bad.

Unfortunately (yes, there's a "gotcha"), passing all the above does not mean that the PSU is good. It's not being tested under any kind of load. But if the fan doesn't turn on, the PSU is dead.

 

[prelude2250]

go buy a $10 PSU tester