power supply problems

[bwarner]

I put a new motherboard in my Pentium III PC (ATX case). After I plugged everything into the MB, I tryed to power it on. There was nothing from the power supply - it was apparently dead. I assumed that somehow I had shorted out the power supply and that it was ruined. I had another power supply in another PC that I knew was good. I removed this power supply, but before I put it into my PC I plugged it into a power cord just to test it. I got nothing again -apparently dead. Can someone tell how I am apparently ruining these power supplies? If you plug in a power supply outside the case, shouldn't at least the fan spin on it?

Barry

 

[franklin97355]

Not necessaraly. Make sure you have some load on the power supply. I would take the parts out of the case and hook them up on a piece of cardboard to test before installing them.

 

[bwarner]

Thanks for the reply. When you say "take the parts out", do you mean like plug a hard drive into the power supply?


Barry

 

[franklin97355]

By take the parts out I mean remove the motherboard from the case and attach only the powersupply, cpu and memory. this should run but not boot. next add the video and floppy. If you can get to a dos prompt add the hard drive. If all this works put it back in the case and test it again.

 

[rezeldazel]

Is it ATX, it will not work unless it is connected to a board, The board will trigger the power to turn it on. You can check it independently using a voltage tester.