[SOLVED] PC only boot after PSU green black wire check

[h0007]

Hello,

I have a mystery to submit to you. Yesterday I put my PC to sleep. It fails weirdly: the LED shows that is was not in sleep (still instead of blinking), but all fans were stopped. After several try to put it out of sleep, I hard shut the computer. Since that operation, Powering ON the PC is impossible, pressing the case button or the motherboard start button does not do anything (no fan activation, nothing). I cleared CMOS in vain. When the PSU is plugged on the motherboard, some ambient light are powered ON (sound card light in red).

Troubleshot: I unplugged the motherboard from the PSU, then I connect green & black wire, the fan of the PSU works (PSU seems OK).
I plugged everything back to the motherboard, I hit the case power ON button, the PC boot normally.
I shut down the PC. Then I press the case power ON button, the PC does not boot.
I repeated the green & black wire test, then plugged everything back and power ON with the case: the PC boot.

Do you see what could cause that kind of problem? Thank you very much for your help, your consideration.

Regards.

 

[cin19]

Maybe the case power button has problem. So check out the wires.

 

[h0007]

Hey Cin19, thanks for your reply. I hit the button of the case but also the one directly onto the motherboard, wouldn't that mean that the problem is not button of the case related?

 

[cin19]

About just unplug the 24 pins power cable, then plug it in again, but don't connect that green/black wire.
If the PC will not boot, after unplug and plug back the 24 pins cable. But the PC can boot, after you connected the green/black cable only, and plug back the 24 pins cable. I think something wrong about the power, like the wire( modular cable ), MB/PSU/case, or the short circuit.

 

[h0007]

About just unplug the 24 pins power cable, then plug it in again, but don't connect that green/black wire.
If the PC will not boot, after unplug and plug back the 24 pins cable. But the PC can boot, after you connected the green/black cable only, and plug back the 24 pins cable. I think something wrong about the power, like the wire( modular cable ), MB/PSU/case, or the short circuit.

Sorry for delay I will try that tonight when back home. Thank you for your help.