Short Circuit while CPU-pwr connected

[JoNNyTwitch]

Hi ,

 

as you can see in the title, i was able to narrow down the problem.

When i leave the CPU-pwr connectors unplugged then the maiboard is starting.

But the way it starts isn't usual, cause the fans are spinning nonstop and i also can't power the PC off anymore.

Except when i turn off the PSU.

That's the build

 

CPU: AMD Ryzen 9 3900x

Motherboard: MSI MEG x570 ACE

RAM: G.Skill TridentZ 4x8gb 3200Mhz

GPU: MSI GeForce RTX 2080TI GAMING X TRIO

Case: CoolerMaster Cosmos  C700M

Storage:OS(Samsung 960 EVO 250 GB) Data(Seagate SATA 2TB)

PSU: 850 Watt be quiet! Straight Power 11 Modular 80+ Gold

Displays: 4 different Displays

 

Thanks!

[Vishera]

There are a lot of variables and suspects here,

Possible culprits:

CPU,Motherboard,PSU

[Spotty]

22 minutes ago, JoNNyTwitch said:

When i leave the CPU-pwr connectors unplugged then the maiboard is starting.

But the way it starts isn't usual, cause the fans are spinning nonstop and i also can't power the PC off anymore.

Except when i turn off the PSU.

What happens when you power it on with the CPU power cables? Anything? Do the motherboard debug LEDs show anything?

[JoNNyTwitch]

Some more input for you:
When i start with CPU cables in, the PSU immediatley shuts off, doing a 'click' sound.

Just the mainboard PWR button shows and i can't start again.

I first have to turn off the PSU wait some seconds turn it back on again,

then i can try to boot again, with the same result.

I also tried another port on the PSU no difference.

I tried it with just one of the CPU cables, then i swaped the port on the mobo.

The only new thing to the setup is that i changed the RAM, but even with the old DIMM's no boot.

 

[seagate_surfer]

13 hours ago, JoNNyTwitch said:

Some more input for you:
When i start with CPU cables in, the PSU immediatley shuts off, doing a 'click' sound.

Just the mainboard PWR button shows and i can't start again.

I first have to turn off the PSU wait some seconds turn it back on again,

then i can try to boot again, with the same result.

I also tried another port on the PSU no difference.

I tried it with just one of the CPU cables, then i swaped the port on the mobo.

The only new thing to the setup is that i changed the RAM, but even with the old DIMM's no boot.

 

I hate when that happens! Not this problem in particular but when you are doing something else on the computer and a new problem appears. The rule I have for that is: What a coincidence, it failed just when I was fixing my computer!  In other words, it would have failed anyway, but it's a big coincidence when something else is broken when you repair the computer. 

Try to reset your MOBO, check on the manufacturer's website how to make it or remove the MOBO battery for a day. Also try cleaning your PSU fan, you can open it and unscrew the fan to clean it properly and even wash it, only the plastic parts, of course. Then, the next day, when it is completely dry, place it back. Your problem is very rare unfortunately.

 

[JoNNyTwitch]

Sooo i did some testing (minimum setup) and i found the Problem.

It is the PSU to CPU connector cable. After i exchanged it, the Mobo booted.

So for this lessons learned i would say: Check your cables

Thank you guys!

 

[seagate_surfer]

On 11/18/2019 at 1:15 AM, JoNNyTwitch said:

Sooo i did some testing (minimum setup) and i found the Problem.

It is the PSU to CPU connector cable. After i exchanged it, the Mobo booted.

So for this lessons learned i would say: Check your cables

Thank you guys!

 

Oh well! We sometimes go so deep into details that forget the basics.  Thanks for the reminder!