Power Supply Issue

Hey,

I've got a power supply that is acting a bit weird. When I plug it in, the computer turns on immediately and powers up. (I.E. you don't have to push the power button). The previous motherboard in the computer went bad and I'm wondering if the PSU was the reason it went bad. What would cause the computer to come on immediately after being plugged into power?

 

check the power button, it could be stuck in....

 

I know this might be a dumb ? but has this been doing this since you changed the mother board,are you sure the wires are in the right place for the on button? Just a guess.I wouldn't think it would be the power supply because i'm sure the relay for the power is on the mother board. Chuck

 

It's probably a Power option setting in BIOS

 

My system will do that every now & then.......only after I been messing with the system though.

Why it does is another matter & seeing as it only does it after some bizzare tweaking.......well....

Thank goodness for backups.

 

The weird thing is, my old motherboard worked fine, then one day it just started doing this, then it stopped working altogether. I'm worried that this will happen with the new motherboard I just got. Any ideas? Should I just go for it?

 

Did you check that?

 

I would go to the ON button.Does your PC have a restart button on the front buy the on button,If so you can use the restart button as on button.Just hook the restart(or reset)wires from the case to the mother board were the power on goes.and don't hook up power on wires from case. Chuck

 

Will your PC shut down the normal way or do have to pull the plug?Just woundering chuck

 

if you have a power button that stays in if you press it, then comes out again when you press it a second time, it could be that you wired it the wrong way round so when the button is off, its actually on?

 

I'v come accross this issue a few times,9\10 its cheap power supplies that do it,they fake the 5v power good line,instead of it waiting for the power good signal coming from the motherboard its directly hooked into the 5v line of the power supply,it causes the computer to start up before the voltage has settled down,these cheap power supplies also seems to fire the computer up sometimes when you flick on the AC,this is really bad and can mess up your computer easily

Unhook the power supply from the computer completely, ground the 5v power on,on the main motherboard plug 'green wire' to any ground 'black' using a bent paperclip the power supply should come to life,now with a testmeter stick the negative probe in any black and the positive in the grey power good if its giving out 5v thats your culprit as its connected to a 5v rail and shouldnt be