Question Gigabyte Aorus z390 Pro - won't boot

[Alimonc]

Hello all

I recently made the move to upgrade my system. Purchasing a new motherboard, CPU and RAM.

Specs are:
MOBO - Gigabyte Aorus Z390 Pro
CPU - i7 9700k
CPU cooling - Corsair H50
RAM - Corsair LPX DDR4 2x 16GB 2666 mhz
PSU - Corsair 850w
GPU - RTX 2080

Building everything yesterday, I went to turn on my machine and nothing happened.

When turning on the mains a very quick flash lights the up LED's on the motherboard then no other lights are illuminated. I have tried the PWR connectors, swapping PWR with RST to see if that works but nothing. The PWR connectors on my case have always been a little fiddly though, sometimes where I have to pull out the main and reconnect to get it to boot. I removed the GPU and still nothing. Tried each RAM to see if that was the problem, nothing. The computer was working fine with my previous build, so I can't imagine it's PSU related.

Since I have removed the water cooling mount around the CPU and found a slight scratch on one trace line - photo here - did I over tighten the screws perhaps and this is causing the board to short and not boot? also, might I have done further damage the RAM?

Any other suggestions for what I could do to find the source of the problem?

Thanks in advance!

Alistair

 

[alexoiu]

Hi, Try testing the board outside the case, to rule out a short.

 

[Alimonc]

Hi, Try testing the board outside the case, to rule out a short.

Thank you - I'll give that a go.

There's no chance the CPU cooler could be causing a problem? Over tightened perhaps?

 

[alexoiu]

I suggest firstly testing outside the case, only CPU and CPU cooler installed, and then deciding.

 

[Alimonc]

I suggest firstly testing outside the case, only CPU and CPU cooler installed, and then deciding.

Thank you Alex - would you try and power up using the case pwr button or using the screwdriver method? here -

View: https://www.youtube.com/watch?time_continue=14&v=FuPZlliGqBw

 

[alexoiu]

Yes, no risk involved. It's what the power button does when pressed: shorting the 2 pins.

 

[Alimonc]

I just did as suggested. Removed the mobo from the case and only attached cooler - lights turned on again when I switch on the mains, but no luck with booting. I used the screwdriver and still nothing... Any ideas for what to do next?

Here's an image to show the setup -

https://imgur.com/a/NTK1qbg

View: https://imgur.com/a/NTK1qbg

 

[Alimonc]

Okay - small update. Some signs of progress!

The top left of the board there's 2 ATX slots – 4 x 12v ATX & 8 x 12v ATX – when I removed the cable from the 4 pin slot, only booting with the 8 pin , the mobo booted. however, when i then put in the other cable, it didn't boot. so could be the cable?

Do I need to be putting power into both the 4 pin and 8 pin ATX slots?

 

[alexoiu]

No, it should boot with the 8 pin only. What label is on the cable for the 4 pin? Is it a 4 pin, or a 4+4 one?

 

[Alimonc]

I see, okay that makes sense. The computer is now up and running. Which is great news! Thank you for all the help.

The cable is a 4+4 one with a fixed 8 pin at the other end - I was putting the 8 pin in the PSU and then splitting the 4+4 to connect to the mobo

 

[alexoiu]

Theoretically, it should work, unless wrongly connected.

 

[Alimonc]

Strange. Well, at least it's all working. Thanks again for all the help.

 

[alexoiu]

You're welcome.