Question System starts for a few seconds then shuts down ?


Nov 22, 2020
When I press the power on button, the system starts for a second, all fans start spinning (cpu cooler, gpu,psu, case fans) and then it just shuts down. I replaced my psu with a new 550w one which is better than my old 450w but I still have the same issue.

Things that I have tried that did not work:

  • push all the cables and components firmly in place
  • Reset Cmos (battery out for 10 mins)
  • clr_cmos with the screwdriver on the motherboard's bumps
  • swapped the two memory dims that I have in a the slots. Tried each slot with each dim, tried both dual channels with both dims
  • dusted every single component and cleaned with technical alcohol
  • applied new thermal paste to the cpu and gpu cooler
  • swapped psu with a new one
  • readjusted the pressure on the cpu cooler
  • taking out components one by one to see which one could be the faulty one, first gpu, then m2, then HDD, even the CPU with only components connected being a Ram dim and the psu, after that I even took out the ram dim and the system keeps on booting for a few seconds then it just shuts down.
  • tried multiple power cords and different wall plugs
I am exhausted and I really wish someone could help me on finding a solution.

My specs:
-Gigabyte z170 K3 motherboard
-16gb DDR4 3200 HyperX ram
-550w PSU

Thank you
I am exhausted and I really wish someone could help me on finding a solution.
Most likely something is shorting out.
Note - with modular PSUs you can use only original cables. No swapping around cables from different modular PSUs (or you can damage your hardware).

Have only single ram module installed.
Disconnect all cables from USB / Audio headers on motherboard.
Disconnect all HDDs/SSDs.
Remove discrete GPU from system.
Have only motherboard power connected 24pin + 8pin CPU power.
Have only CPU fan connected. Disconnect all other fans.
Have PC beeper connected.
Try to start your system.

If that still doesn't do it, then remove motherboard from pc case and try to start it this way.

Also go through this checklist.


Nov 22, 2020
Oh wow I feel stupid not installing the cpu.
So, I did everything I was told in this thread and it actually booted somehow. I couldn't pin point the exact problem, but I think it was a multitude of things combined that made my system behave that way.

Last thing I did was putting the ram in the A2 slot, installing the cpu and the cooler, I then reset the cmos once again, and the led lights from the motherboard turned on once I pressed the power button.

Thank you everyone for your time and help :)