# Odd 8 pin Power issue with Z490 and i5 10400



## natsukirei (May 29, 2020)

So basically, its like the PC is trying to spark itself on but fails a few times then eventually turns on. its very quick, like a millisecond.
So i tried moving the 8 pin power around to the CPU.

so my psu cpu power cable is 4+4 pin, and the motherboard has an 8+4 pin setup
When plugging one of the 4 pins into 4 pin CPU_PWR2 slot, it boots right away, no issue.

Then trying the other 4 pin in the same PWR2 slot, it does the spark thing were it takes a few tries
And when both in the 8 pin, it sparks again.

I am completely lost why this might be happening, whether its the CPU or a power issue with the Power cable.
If CPU_PWR2 was enough to run the pc id just run that lol

i checked on Linus tech tips discord and they said the power is to much for the i5 10400 and to use the 4 pin


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## EarthDog (May 29, 2020)

natsukirei said:


> i checked on Linus tech tips discord and they said the power is to much for the i5 10400 and to use the 4 pin


Bwaaaaaaaaaaaaaaaaaaaaaaaaaaaaahahahahalolololol, NO. It doesn't work that way. Whoever said that is absolutely clueless.

The manual should have you put the 8-pin/4+4 in CPU_PWR1.

If this does not work, I would RMA the board.


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## ERazer (May 29, 2020)

EarthDog said:


> Bwaaaaaaaaaaaaaaaaaaaaaaaaaaaaahahahahalolololol, NO. It doesn't work that way. Whoever said that is absolutely clueless.
> 
> The manual should have you put the 8-pin/4+4 in CPU_PWR1.
> 
> If this does not work, I would RMA the board.


^this

i think the CPU_PWR2  is for extreme OC not necessary for your CPU


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## Caring1 (May 30, 2020)

If your system tries to boot a few times and fails, then eventually boots, that indicates a Ram issue.


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## natsukirei (May 30, 2020)

Caring1 said:


> If your system tries to boot a few times and fails, then eventually boots, that indicates a Ram issue.


 

i ran windows memory diagnostics and stress testing and i couldnt find any obvious issues with the ram.

Its very odd how it happens, its like the pc sparks on for a millisecond the fans manage to do 1 rotation spin and then it stops and tries again until it eventually comes on


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## puma99dk| (May 30, 2020)

Once again 4+4pin for CPU power is usually the one to the left closes to the I/O on a motherboard if it has an extra 4 or 4+4 pins it's not to be used under normal daily use.

This is what I been informed by different motherboard manufactures but it can very from platform to platform at least for the normal LGA115x and Socket AM4 boards it's like this.


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## Caring1 (May 30, 2020)

natsukirei said:


> i ran windows memory diagnostics and stress testing and i couldnt find any obvious issues with the ram.
> 
> Its very odd how it happens, its like the pc sparks on for a millisecond the fans manage to do 1 rotation spin and then it stops and tries again until it eventually comes on


Wrong timings can cause that even if there is nothing wrong with the Ram.


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## natsukirei (May 30, 2020)

Caring1 said:


> Wrong timings can cause that even if there is nothing wrong with the Ram.




Interesting, I watched the ez debug lights, usually on a successful boot it flashes white, CPU, ram, power, post

When the issue happens, the CPU flashes white then when the ram light is meant to come on is when the issue occurs

I did notice my ram kit was running at 2T, on my ryzen it was 1T


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## puma99dk| (May 30, 2020)

@natsukirei can you please fill out your System Specs it's makes people easier to know what components you have or at least list them in your thread.


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## natsukirei (May 30, 2020)

puma99dk| said:


> @natsukirei can you please fill out your System Specs it's makes people easier to know what components you have or at least list them in your thread.



Oh so sorry about that, i have updated my system specs


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## natsukirei (May 30, 2020)

Update

So i tried removing the CMOS Battery, and again it did its 6 time on and off , cpu light passes and the ram light wont come on until a boot around the 6th time when ram passes and it boots up.

Changing ram slots had varying effects, i decided to take both sticks out and try one in each slot, sometimes it would boot right away when switching the power off and on via the PSU button,  and sometimes it would do its sparky effect twice and on, and sometimes 6 times

Either way, moving the ram kept having effects, very odd effects

Now once on, i have run cinebench, Intels Processor Diagnostic tool, prime95 and Heaven benchmark runs, and everything has been successful, and now when i switch off and on, it does its sparky thing once and comes on 2nd try.

Interesting results.

new report

Turns out their looks like theres a pin bent backwards, i dont have the expertise to fix this so im hoping my local pc store will take it back



http://imgur.com/a/0PUbnIm


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