Newly built PC doesn't turn kn

[Toad Bloke]

A bit of backstory, I've never built a PC before but I bought a custom made on a year ago this year I decided to upgrade it in a major way with a new motherboard, GPU, CPU and power supply. 

 

As this was my first time building a PC I followed a guide posted by LTT and I think I followed it fairly well but whenever I switch the power switch on the power supply the motherboard's RGB LEDs switch on then immediately off. 

 

I'm unsure of the cause of the issue but I think it is the motherboard as I've removed the GPU, took all the RAM sticks out except 1 and swapped them around, removed both the SSD and the hard drive and tried another power supply. 

 

Parts List:

Ryzen 7 3700X

RTX 2070 super

Gigabyte X570 Aorus

Corsair RM 650x

Corsair Vengeance LPX 4 x 8GB 2133MHz

Corsair H100x

Toshiba 5TB HDD

1TB Intel 760p 

[TheGlenlivet]

Sounds like you've narrowed it down to the MOBO, but check your CPU power cable and 24 pin and make sure they are correctly installed and seated all the way.  That and reseat the CPU, just to make sure that it's in correctly too.

[Brooksie359]

So you switch the power supply on and then you attempt to start the pc and it doesn't go? Try making sure the CPU fan is in the correct cpu fan header as sometimes the system will shutoff after initially starting up when it detects no fan is connected to the CPU fan header. 

[Sjaakie]

Are you sure the front panel on/off button is securely hooked up to the motherboard? Try shorting the pins directly with a screwdriver or some other metal.

[Toad Bloke]

1 hour ago, Brooksie359 said:

So you switch the power supply on and then you attempt to start the pc and it doesn't go? Try making sure the CPU fan is in the correct cpu fan header as sometimes the system will shutoff after initially starting up when it detects no fan is connected to the CPU fan header. 

No when I switch the power supply on the motherboard's lights switch on then immediately off I don't get a chance to press the power button and it does nothing anyway.