Motherboard Leds turning on but nothing else in the pc

[shadowstorm9199]

Just built a custom gaming pc and after completing the build i plugged in and turned on my power supply, making a red led start flashing on and off on my motherboard. However after pressing the power button nothing happened, no sounds, no fans turning, no other lights except the motherboard leds. I tested the psu and it is working, I checked the panel header and the power switch is placed properly and I made sure that all of the power connectors were well connected. I am puzzled about what is causing my newly built pc to not respond to anything, and if you have any ideas I am really interested in them. My pc build is the following:
Intel Core i5 8600k
Noctua NH-D15 (1 fan)
ASRock Z390 Phantom Gaming SLI/Ac
G.Skill Ripjaws V DDR4 3200 16gb (2x8gb)
Shaphire Radeon RX Vega 64
Samsung 970 Evo 500gb
SeaSonic Focus 850w 80+Platinum
Thermaltake View 31

 

[alexoiu]

Try testing the board outside the case, to rule out a short. Check also the 24 pin power cable if properly connected.

 

[shadowstorm9199]

Try testing the board outside the case, to rule out a short. Check also the 24 pin power cable if properly connected.

 

[shadowstorm9199]

How exactly do I test it outside of the case, I am new to pc building. I have checked the 24 pin cable, replugged it in multiple times and it is well plugged.

 

[alexoiu]

Remove the board from case and put it on its box. Start it by shortly touching with a screwdriver the 2 pins on the board corresponding to the case power button. See if the CPU fan starts spinning.

 

[shadowstorm9199]

Remove the board from case and put it on its box. Start it by shortly touching with a screwdriver the 2 pins on the board corresponding to the case power button. See if the CPU fan starts spinning.

 

[shadowstorm9199]

I tried touching the pins with a screwdriver with my power on and absolutely nothing happened what should I try next?

 

[alexoiu]

Try testing the power supply: https://www.youtube.com/watch?v=5FWXgQSokF4 See if a fan connected to it does spin.