larya wrote:
Is there a group for repairing computer power supplies?..

No, but you're on-topic in here.
You can find lots of info about ATX power supplies he
http://en.wikipedia.org/wiki/ATX


Question... I have the power supply out of the computer...
Besides pluging it in... how do you turn it 'on'...
The front panel on / off switch connects to the mother board..
How can I turn the power supply 'on' at the power supply?...

You need to ground the power-on signal, which is the green wire.
If you want to use the PSU as a bench supply, you can simply snip the
green wire from the back of the ATX connector, & solder a switch between
it & one of the black wires.

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