My computer automatically switches off, no bios logo appears.

[newbieneel]

The cpu fan spins for 3 sec then stops. Power led turns green, stays green then becomes off, but power led on mobo stays on. i tried putting the RAM on second slot, disconnecting DVD drive, disconnecting HDD to no avail.
AMD Athlon 64/ ASUS M2N-MX SE mobo/ 1gb DDR2/ Seagate SATA hdd/ LG DVD Multi drive.

 

[Novuake]

Sounds like your Powersupply is giving in.
Whats the Wattage on it?
And do you have a Graphics card?
Have you made any recent changes to your system?

 

[newbieneel]

Sounds like your Powersupply is giving in.
Whats the Wattage on it?
And do you have a Graphics card?
Have you made any recent changes to your system?

PS 300W
No, i have onboard NVIDIA graphics
No, i have not made any recent changes.

 

[Novuake]

I'm still thinking its your powersupply. Try a new one, at the price of PSU's under 400watts its not a waste of money.