PC powers off abruptly

[Jaxx89]

Sorry if I am posting this in the wrong section but I really didn't know where else to post.

Ok my PC config is as mentioned in the below image.

Now as mentioned in the title, my PC seems to be shutting off just abruptly.
It was happening before because of a bad PSU and I had replaced it.
The same problem has started again so this is what I have done.

Disconnected all the drives from the mobo(HDD & DVD-RW)
Removed the RAM modules
Removed the GPU
Now only the CPU and some fans are connected to the mobo.

Power on
No Beeps
Just the fans are running and some lights switched on the mobo
Within a min(mostly a few seconds less than 10), the power shuts off.

WHAT I can't understand now is that which component is the problem. The PSU or the motherboard.


Please help me out.

 

[ko888]

You left out the specification of the most important piece of the puzzle.

What is the make and model of your power supply unit?

Is the CPU or GPU being overclocked at all? If yes, by how much?

 

[WR2]

The same problem has started again

How long after you installed the new PSU did it start happening again?

 

[Jaxx89]

I am so sorry.
The PSU is a Corsair HX850 and was installed in Sept 2011.
The problem started just 2 days back. I ran a AV scan first in safe mode and it was shutting down after few hours then.
Since yesterday it started shutting down every few seconds.

The CPU and GPU are not overclocked.
And I tried resetting the BIOS but still no change.

 

[ko888]

I am so sorry.
The PSU is a Corsair HX850 and was installed in Sept 2011.
The problem started just 2 days back. I ran a AV scan first in safe mode and it was shutting down after few hours then.
Since yesterday it started shutting down every few seconds.

The CPU and GPU are not overclocked.
And I tried resetting the BIOS but still no change.

Is there any code displayed on the motherboard's Debug LED?

Are you using a USB keyboard and/or mouse or PS/2 style keyboard and/or mouse?

What is the USB Keyboard Function and USB Mouse Function BIOS settings set to?

Is the 24-pin ATX main power connector from the power supply unit fully seated (i.e. not stressed/strained/pulled to one side) in the socket on the motherboard?

 

[Jaxx89]

Sorry for a delayed reply. The motherboard was the issue. Gave it for repairs. Got a response saying the BIOS chip is malfunctioning.
Now the only option is to get it repaired or replaced.