[SOLVED] PC won’t power when power to CPU-PWR plugger in

[RobioAXP]

Strange one here. I had a working PC that I’ve been using for months simply stop on me. Went to turn it on and got maybe a split second of power and then nothing. After multiple attempts and unplugging and trying each component, finally gave up and considered it was either mobo or CPU (I tried with 3 different power supplies all 450 - 650w). So decided to replace both including new DDR4 RAM.

Just installed brand new mobo and cpu and having same issue. I’m now certain power supply, motherboard, and CPU can’t be at fault. When I plug everything in except power to the CPU-PWR1 connector on mobo, the PC gets full power (just doesn’t post). Holding power button on case won’t turn it off, so must turn off switch on power supply. As soon as I plug in 8 pin into CPU_PWR1 and turn on, I’m back to the split second power and then nothing. I’m not using the CPU_PWR2 4pin, but I’ve read that wasn’t necessary. Any ideas?

Motherboard: MSi MPG X570 Gaming Plus
CPU: AMD Ryzen 5 3600
Power Supply: Coolermaster 600w silent pro
Graphics: GeForce GTX 1070

 

[DSzymborski]

How have you become certain the power supply isn't at fault? That it works when the CPU power isn't connected doesn't mean much concerning the power supply.

 

[RobioAXP]

I’m only ruling it out because I’be tried 3 different power supplies to the same effect. The one thing I haven’t done is try powering up with everything completely outside the case. for both the old mobo and new one I used the same gold risers to attach he mobo. They all seemed to line up correctly but perhaps I should try that?

 

[Karadjgne]

What else is plugged in when you do this? Keyboard, mouse, external drive? anything else usb?

 

[RobioAXP]

Okay, not sure what happened with my original motherboard issue, but when the halfwit human doesn’t realize that the power to the CPU_PWR on mobo isn’t actually pushed in enough and properly attached, then the outcome makes perfect sense. Thanks for trying to help, but I think it’s working now. Just need to play around with setup to get Windows up and running I think.

 

[DSzymborski]

I’m only ruling it out because I’be tried 3 different power supplies to the same effect. The one thing I haven’t done is try powering up with everything completely outside the case. for both the old mobo and new one I used the same gold risers to attach he mobo. They all seemed to line up correctly but perhaps I should try that?

Breadboarding is always a good idea. I like removing as many variables as possible.

My fault on the power supplies; my eyes totally skipped over the part where you tried three different ones, so that's on me.