Help needed to detect system fault!!!!

[BULLZI]

......And my bad luck continues.

Yesterday night, my machine turned off suddenly. Motherboard got power as I can see my soundcard Supreme Audio FX II glowing blue. But as I press power button on my cabby, the psu (Tagan BZ 800 watt) and one of my cabby led fans (Antec 900) blinks and then turns off. From the second time onwards, as I press power button, nothing happens.

I thought for a time that the power button has gone wrong. My motherboard (Asus Maximus Formula) has got onboard power switch. I tried using that button too but the result was same.

The weired thing is that when I turn off the main switch on the switch board and turn it on again, for the 1st time, when I press power button on my cabby, the psu and cabby fan blinks for once as if its going to turn on and then the system turns off.

I also checked with the power cord of the psu and used a different power cord. The result was the same.

Sometimes, even my motherboard is not getting power as the Audio Card led doesnt glow when I turn on the psu.

I was using my Corsair HX 620 watt power cord with the Tagan psu as the TAGAN power cord has no ground pin.

Now I cant detect where the fault is. Please suggest me how I can detect where the fault has occured. I am rite now quite confused.

Thanks.

[channabasanna]

Even i had used a different power cord for my CPU, as my coolermaster 600w PSU had only 2pins, (No Earthing pin).

[nish_higher]

i think its a PSU fault but still-
1.remove the cell from the mobo and reinsert it.
2.u using a UPS?
3.try connecting without UPS
4.try using a different psu

[romeo_8693]

Well first clean ur RAM with a eraser and try to boot, if it fails and ur lucky enough to boot for a while check if any of ur IC's are getting too hot be carful not to induce static though.Hope ur fan is working fine at correct RPM.

[BULLZI]

Got the fault. Its my gfx card. I ran my system with my friend's 6600GT and its working fine.

Can it also happen that my psu cant handle the load of my gfx card(HD3870X2)?

[realdan]

it could be the case if the graphics card is OK

tagan..i would never get this in place of corsair, antec or coolermaster..but i havent used it to really comment on its reliability