Question After turning off PC and coming Back it won't start

[BackdadSchuh]

Hi everyone, so a week ago I got myself a new Motherboard the MSI B450 Mortar MAX and everything was fine until yesterday, I went out and turned my PC off just to come back to it not turning on.

CPU:Ryzen 5 2600x

Motherboard:MSI B450 Mortar Max

Ram: 2x8 Crucial Ballistix BL2K8G32C16U4B 3200 MHz

SSD:Kingston 240 GB (sa400m8240g)

GPU:RX 570 8GB "PHANTOM GAMING"

PSU:CSL Modelnr.: 57361/CSL18059 with Max 500 Watt
It's 3 years old

Case:CSL Black Hawk ATX-Tower

The "EZ" debug Light for the CPU was red
I already tried the usual Stuff:
Cleared CMOS
Tried out a different CPU
I removed everything but the CPU
Even the RAM but the CPU debug light still was the only light that was on
Then I swapped back to my old Mobo
(Asus Prime a320m-k)
and my beeper finally have me a beep
it was one single short beep
Apparently it means that something is wrong with my GPU but it can't be that because I tested it on another System and it worked there
Im new to upgrading PCs and I really am out of Ideas of what to do
I suspect it's because of the PSU

Thanks in Advance
If more Specs are needed I will provide them

 

[Lutfij]

Welcome to the forums, newcomer!

When you migrated to the new motherboard, did you reinstall the OS? If not, that's your primary issue. It's customary to include your full system's specs to eliminate guess work. Please list them like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:

include the age of the PSU, apart from the make and model of the unit.

 

[BackdadSchuh]

Hi I updated my specs list now!
I didn't reinstall the OS because the new motherboard worked for a week, with me not having to reinstall anything it just stopped working when i came back from a walk.