Power supply won't shut off

I have a computer I built last year and it is starting to give me a problem. When I go to shut off the computer through windows.. the computer turns off except the power supply. I have to manually unplug it from the wall and cut all power for it to completely shut off.

I thought it was the motherboard going bad and not telling the power supply to turn off but I completely took out the PSU from my computer and had it hooked up to nothing and as soon as I plugged it into a wall outlet the power supply turns on. Do you all think it is the power supply? I think I ruled out the mobo by unhooking it and trying that.

 

Sounds like a psu to me. I had a real cheap one do this to me a while back.

 

Yes, The PSU. Check the Green line Maybe it touch the Black line and this makes it run 24/7

If it is a cheap PSU, Get new one and enjoy peace of mind.

Good luck

 

I've got a Hiper PSU that does this with windows, bizarrely it always turns off when shutting down from Ubuntu though so I'm convinced there's something within xp that can cause this. Hold the power button for 4 seconds, that usually puts it to bed.

 

Then the PSU is fine. Check your windows, Maybe a Virus or some thing missing in files or settings. If I were you, I format it and see what will happen.

 

I had this problem with my Hiper... With me, a simple change of modular connectors did the trick, the 4 pin modular one on the actual PSU had a duff pin.

 

you turn your pc off? bizzare...

 

Go to your BIOS and set the setting to default and see if that helps.

 

@ the OP, what make is your PSU/other hardware? The reason it will boot up when you plug it back in iirc is due to a setting in the BIOS, can't recall exactly what it's called but you can choose to power on after a cut in leccy or stay off.

you can't upgrade bits while its on

Tried that several times, with different versions of windows/virus checkers, which is why I'm convinced windows settings have something to do with it, especialy as 'buntu turns off every time I can't work out what setting it is though

 

Does your bios have a "power status after power loss" or similarly worded setting? If that is set to "on" it will automatically power on as soon as you connect the mains (the idea is you can use it on servers so they reboot after a power cut). That could also be causing weirdness after you supposedly "power down"?

 

lucky you, my power unit has just switched off terminally

 

If the PSU is turning on when plugged into the wall but completely disconnected from the PC then it has a problem. Look no further. A PSU shouldn't turn on until it's given a signal to, ie the green wire in the 20/24 pin being shorted to grd (black).

Get a replacement PSU