computer won't boot. Power Led light up even before pressing the botton

digam

Distinguished
Oct 7, 2009
27
0
18,540
Hello,
Last night my pc turned off and now it won't boot up. When I power on the power outlet. The green led on the pc lights up without even touching the pc. When I press the power button on the pc the fans light up but no display. I have a core i3
Biostar motherboard
550w pou
No GPU
4 GB ram
I tried switching the ram slot. Disconnecting hdd. Nothing happens.
Please help me. Thank you in advance.