Is this a Mobo problem ? 2

[ylan]

After changing a defective power supply in my PC ( an old, desktop with Pentium III 800 Mhz CPU ), it refused to boot up . All I saw was the Hard Drive led was always red and the Power-on led was black ( this led is associated with the Power on/off Push button in the front panel of the PC . It supposed to be green when the PC worked correctly) .

1) I checked the HD on another PC . It worked fine (i.e. Windows XP Pro )

2) I checked the new power supply on another PC, it worked great !

I do not touched the flat connection from the Power On/off push button to the mobo at all .

My question :

_What might be wrong with my PC ?
_How do I know if my Mobo is dead ?

As I need to know for sure if I should toss this PC out , your advice is very important for me. Thanks,...

 

[BadFrog]

Sounds like the power button may be bad. You should be able to power up your PC by shorting the two pins that the power button connects to for a brief second.

"Once you can accept the universe as matter expanding into nothing that is something, wearing stripes with plaid comes easy"
Albert Einstein

 

[ylan]

Thanks for the hint . But would you please explain in more detail... I am totally lost by what you said . How can I carry out this operation ? All I saw was a tiny flat female connector plugged onto the mobo . There was a flat cable joining the power button & this connector . Please elaborate ...Thank you ...

 

[wunkunn]

ylan, What BadFrog meant was for you to remove the "flat female connector" from the two pins on the MB. Momentarily short the two pins together with a small screwdriver or other metal object. The machine should boot up at that moment. If it boots, then the problem is with the power on/off button. If it doesn't boot, then the problem lies eldsewhere. (Be careful when shorting the two pins on the MB, that you don't accidently short and fry something else)

 

[ylan]

Thanks BadFrog & wunkunn for your advices !
Nothing happened when I shorted the 2 power pin on the Mobo !! I guess something wrong with the Mobo . Tossing time then ...

Thanks again....

Best regards,

 

[BadFrog]

Thanks for having my back on that wunkunn!

Might be worth double checking that you hooked all the necessary connectors up from ps to mb. In particular the 24 volt connector if it has one.

"Once you can accept the universe as matter expanding into nothing that is something, wearing stripes with plaid comes easy"
Albert Einstein

 

[wunkunn]

ylan. one other thing, if you have a floppy diak drive and the power plug is installed incorrectly, the machine will not boot. Incorrectly installed data cables to hd's and floppy drives can also prevent boot up. Please post the solution when you find it. Good Luck