PROMLG :
ko888 :
What's the brand and model of the power supply unit?
Bitfenix whisper 650W.
The paperclip test worked btw
The paperclip test is not proof that the PSU is functioning within spec. It's only proof that the PSU is not completely dead.
So what is the solution now?
It's the motherboard that sends the PS_ON# signal to the PSU. If that's not happening then there may be a problem with the motherboard. The PSU is also suppose to send a PWR_OK signal back to the motherboard so that the motherboard can determine whether or not it is safe to stay running.