Problem of dell optiplex to power up

[mwagunga]

Hello, i have a dell optiplex CPU and it just went off,when i power it i just hear the power vibration of the fun and hard disk and only one green light on the motherboard.i have tried another power supply but cant work still.can it be the mother board with problem.?

 

[Ubrales]

Are you certain that the other PSU you tried with is a known good PSU?