[SOLVED] CPU doesn't turn on, no movement when power start button pressed

[TonyStark07]

Hi Folks,

First post here. Ran into one problem with my PC. It's not booting at all when power button is pressed.

Here are the specs:
MOBO: Biostar H81MHV3
CPU i5 4 core LGA 1150

Here are the diagnostic I have run so far.

I stripped the motherboard of all accessories. Only ram is connected. CPU fan is connected.

Scenario 1: CPU seated, CPU fan connected, 24pin power connected and 2X2 CPU power connected.
Result: Nothing happens when I short the power pins on MOBO. I do here click on psu but nothing moves.

Scenario 2: CPU seated, CPU fan connected, 24pin power connected but 2X2 CPU power is not connected.
Result: when I power it on, CPU fan moves for like half a sec and then do nothing. sometimes it does this half-a-sec thing 2-3 times and then stay dead.

Scenario 3: CPU not seated, CPU fan connected, 24pin power connected but 2X2 CPU power is not connected.
Results: When I power it on, fan runs continuously until I remove the PSU supply

Scenario 4: CPU not seated, CPU fan connected, 24pin power connected & 2X2 CPU power is connected.
Result: When I power it on, nothing happens

Could anyone plz help me identify the issue. Is it the motherboard, CPU or the PSU which has gone bad?

I have checked CPU seating pins, all pins are good and not bent. CPU also looks good as such. Also replaced the CMOS battery, it was 2.3volt. At that time fan was not budging in all above scenario. I replaced CMOS with new one 3.3volt and reset the jumper. The above diagnostic is performed on new battery.

 

[JohnBonhamsGhost]

not booting at all when power button is pressed.

how are attempting to power on the system?
through case power button,
through an onboard motherboard power button,
or by shorting front I/O power pins?

or the PSU which has gone bad?

only real way to test if a power supply has malfunctioned is to try it in another system and/or try another in yours.

 

[TonyStark07]

how are attempting to power on the system?
through case power button,
through an onboard motherboard power button,
or by shorting front I/O power pins?

only real way to test if a power supply has malfunctioned is to try it in another system and/or try another in yours.

Momentarily shorting the 2 pins on MOBO where the power switch goes.

Yes, I am looking for another PSU to try.