my mother has a dell desktop PC only a couple years old. if i disconect the power cord it will act like it is gonna startup but stops abruptly. after that i get no responce from the power button at all unless i pull the plug for a while.
I am very sure this is a hardware falure problem and dell tech support is no help.
the hardware it-self has not been messed with for months prior to this problem. i have no idea what kind of settings she could have adjusted to fry something, but im sure something is dead. i’ve never seen anything like this.

my question is what should i replace first?

Could this problem be as simple as the MotherBoard battery?
the power-supply unit?
the Motherboard itself?
Bad CPU?
added 9:14 am
i checked pwr button and thats not it