start-up and turn-off & start-up & turn-off indefinitely

[azvnoit]

I've been having problem with my desktop. It's around 4 months old.
Intel DH61WW mother board, core i3, 2 GB RAM, 500GB HDD, AMD Radeon 5450.
My problem is that the computer turns off, there is not a proper shut down. And in a few seconds it powers up but the power led is not on. and there's no display. The processors fan stays in motion and the HDD and DVD drive works but no visual and the power led remains off.
If I disconnect the power supply for few minutes and then try to turn it on it starts up but turns off again after few minutes.
Sometimes it starts up and turns off and again starts up and turns off indefinitely.

I changed the SMPS and cabinet.
Detected a burnt RAM slot, rectified it. RAM is working fine.
Removed Graphics card. Re-installed OS. Still the problem persists.

It would be really helpful if you could assist me in rectifying this problem.
Thank you.

[Sam]

reset BIOS & check if it helps else we'll have to dig a bit more into bios. secondly it can be cause of a bad PSU or faulty front panel (cabinet front panel or F_PANEL in mobo).

[azvnoit]

Reset the BIOS but that brought another problem. As the OS boots, within 4-5 seconds the system crashes and restarts and again the OS tries to boot and restarts again within 4-5secs. I tried loading the initial BIOS settings but the new problem persists. I tried Startup repair which restore the computer but still nothing.

[Sam]

do you have live disc of any linux distro? test your pc with it & let it run for few hours. if it shuts down or restarts, most likely its a motherboard problem.

[azvnoit]

Thanks for the help. I finally narrowed down the problem to the motherboard. As the motherboard was microATX there were loose RAM when the Graphics card was inserted. This caused unusual heat and caused one of the RAM slot to burn. Later the heat was causing abnormal shut-down.