[SOLVED] CPU trips PSU

[roloDev]

I'm trying to finish up my first build, but I am running into an issue with my power supply and my CPU. I have done both basic troubleshooting (connecting individual components to the PSU and powering on/off) and more detailed troubleshooting (taking everything apart and checking if CPU was busted, mobo was bridging somewhere) and I can't seem to find why every time I connect my CPU power the PSU just trips and shuts off. Like I said, this is my first build so I may just be missing something crucial that I am unaware of. For reference my CPU is an AMD Ryzen 7 3700, the mobo is an MSI x570 Gaming Plus, and the PSU is a Seasonic 750W 80+ Gold. I'm also assuming that the CPU power cable for the Seasonic is the one that ends in the two 4-pin connectors. Any help is much appreciated, thanks.

 

[richiestang_78]

Which Seasonic exactly? The FOCUS GX Plus Gold?

For your motherboard you need to plug in the 24pin ATX and 8pin CPU. The 4 pin CPU next tot he 8 pin is optional to my understanding however if your PSU has a cable for it I would use it.

Use the cables labeled CPU with the corresponding ports on the PSU. Page 25 of your mobo manual show where these ports are.

 

[kerberos_20]

if it trips, there is a short somewhere
remove mainboard from case and put it on cardbox
also which cpu cooler are u using?

 

[richiestang_78]

if it trips, there is a short somewhere
remove mainboard from case and put it on cardbox
also which cpu cooler are u using?

Yeah forgot to mention what he said. You did install the motherboard standoffs (spacers) onto the case then put the mobo on the standoffs. Many cases have them pre-installed but some don't.

 

[roloDev]

Thanks for your replies. Yeah, the case I got has the spacers built in so all I had to do was put the mobo in and secure it. I’ve actually taken it off and re-adjusted it (but I haven’t checked it on cardboard).

The PSU is the Focus series from Seasonic, and the 24-pin works fine. The CPU cooler fan turns on (I’m using the stock Ryzen cooler for the 3700), and so do the other fans. But I didn’t see a cable strictly labeled CPU, but rather N. It was one cable that split into two 4-pin heads, which I connected to where the mobo manual said the CPU power should go.

 

[roloDev]

UPDATE 02/18: I got a second PSU and have run the same troubleshooting procedures. Taking the whole motherboard out of the case and putting it on cardboard. 24-pin connection still works well, but the 8-pin CPU trips the new PSU as well. Looked at the back of the motherboard and nothing looks bent, melted, or burnt. Could it just be a faulty CPU power port?

 

[Greatli]

You are plugging the 8pin in while it is off, right? Could just be a motherboard defect

 

[roloDev]

You are plugging the 8pin in while it is off, right? Could just be a motherboard defect

Yes, somebody asked me this too. I guess I should word things better. Yeah, I turn the power off every time I remove/connect a cable. Sadly I’m also thinking it’s a motherboard defect, because after taking out the board from the case and inspecting it on cardboard I get the same results, and I see no pins that seem broken, twisted, or singed on the back.

 

[roloDev]

Update 02/20/20: The cause of all of this was the motherboard. I got a replacement mobo sent to me by MSI and it turns out that the old motherboard had an 8-pin CPU connector was faulty. New motherboard is working just fine. Thanks to everyone who took the time to respond to this thread!