Motherboard issue

[pedromendez]

PC specs
Msi - 870-G45
AMD Phenom II x6 1095T
2X2gb ram (tried just one stick and switching them around, still nothing)
radeon HD 6790
500GB HDD
550W psu + serveral others if need be.

I've recently completely rebuilt my PC to try and see if this will fix an issue i've been having the past 12 hours and it has made no difference (The pc will not boot all it does is spin the heatsink for less then a second and a blue light will flick on then off, the only way to make the motherboard do this action again is to unplug the PSU and wait around 2 mins to try again), i can only imagine there is a problem with either the CPU or motherboard but i have no idea which, does anyone know how i could isolate the component that is casuing this issue?

Thank you

 

[avenseth12]

This sounds like a PSU failure. Who makes your PSU? Do you have another PSU to try?

 

[smorizio]

if the power supply itself did not fail. (tried with a spare). then is sounds like there a part in your system that causing a dead short. I would start by unplugging power to all the drives and removing the video card and any extra cards from the system and extra ram. you want to bare bone the pc to see if it will power on. if is does not..check to see if your computer case uses a small daughter board for the on switch and front headers. could be this small board or the on switch went bad. with no video video card or ram..and the mb outside the case with a power supply. if there not power it could be the mb or cpu. most times it be the mb...but i see cpu die too from over clock failures.

 

[pedromendez]

I have tried three separate PSUs and all have the exact same issue, i have take the motherboard out of the pc case and tried it with only the CPU and one stick of ram and again same issue. All i'm trying to find out now is whether i need to replace my cpu or motherboard and i really have no clue which is at fault. (I have never overclocked my CPU) Both parts are both the same age as i bought them both from scan.co.uk