Should my power supply fan be spinning?

[Spocko]

That topic is bound to pull somebody in here!

I just bought an Enlight 7237 case, with a 300W ps. It seemd to be getting power at first, but now it appears dead.

I tried setting up my MSI K7T Turbo, and all the other hardware, but the board would only stay on for about 2 seconds, everything seemed to have power, hard drive, cd-rom, keyboard, but then the whole system would power off. I tried changing the cpu fan, becuase it wasn't running. The new fan spun, but the power still shut off after 2 seconds. I tried moving the cmos jumper, because there was some confusion over which setting would clear cmos. Since then when I plug it in, and turn on power, nothing happens.

My quesion is, if I disconnect everything from my power supply, and turn it on, should the power supply fan still spin? Is the power supply smart enough to know that there is no motherboard attached? I checked the voltages bewteen pin 1, and pin 3 on the ATX 20 pin connector, but there's not even a twitch of power when I flip the switch. Did my PS die on me?

 

[fargus]

You can't power up an ATX supply without an attached load. You need to have a mobo or a power supply tester attached.

 

[Rifter]

thats not totaly true, you can power it on by shorting the PS-ON lead(which is the forth wire from the left on the top row when looking at the ATX connector with the clip on the top) to any ground(any black wire, but preferably the PS ground(usualy grey)) a paperclip bent to shape works well for this. Your PS should tell you what color wire is PS on(which is always in the location i described) and PS ground(which tends to move around PS to PS but any black ground wire will work for this test), short them with a Paperclip(or anyhting condictive) and turn the switch on and it will power up.

 

[Spocko]

Thanks for the help. It turns out that my PS is fine. My system is powering up ok now. I think it was just some stupid mistake of mine. On my PS, the pin 14 (PS_ON) is actually black, and the one above it (pin 13) which is supposed to be a ground, is white. I won't worry about that now though.

 

[Mday]

a well designed PS should not power up without a load. it's just wrong. AT or ATX, if it powers up without a load, i would throw it away...