Question No POST, no beep, no boot, tested RAMs, GPU, PSU with another computer and they work. Is my motherboard or CPU fried?

[Xandria]

Hello everyone!

I have this system since 2020, woked normally for all this time but now I get no POST, no beep and black screen.
PC turns on with its power button, fans starts to spin, power LED turns on but I can't turn it off by long pressing the power button, have to switch off PSU switch.

I tested all the components in an old computer (A intel core 2 duo) that I have and they all work, PSU, GPU and RAM sticks all intact but couldn't test the CPU as it's a different socket.
Tried putting the other PC's GPU (Radeon HD6450) and I got the same.

Tried booting with only 1 RAM stick in either slot with SSD unplugged but nothing, with both my GPU and the HD6450. Tssted both RAM sticks.

My configuration:
Motherboard Asus A320M-K
CPU Ryzen 7 2700
Deep Cool 240mm liquid cooler
RAM G.Skill Aegis 16GB DDR4 3200 (x 2)
GPU Nvidia Geforce GTX 1050 ti
PSU Silverstone NightJar NJ520 520W 80 Plus Platinum

So if all components work this means it's either the motherboard or the CPU that is at fault?
A friend of mine said it's unlikely that the CPU got fried because it would have beeped and it's more likely that the Motherboard is at fault....or worst case scenario both at the same time.

What should I do, should I buy another motherboard? Any reccomendation? The A320M-K I have is limited to 32GB, I would like to mount 64Gb in the future.

Thank you

EDIT: spelling

 

[realpao]

Test your motherboard with another CPU. If you don't have the part, go to a repair shop.

 

[Dark Lord of Tech]

Was that PSU released like 10 years ago?

 

[Xandria]

Was that PSU released like 10 years ago?

Not sure when it was released, but I got it new in 2020 cause I wanted a passive silent PSU but didn't want to spend too much and found it on some ecommerce shop online as an occasion.
Had the doubt it could be faulty but I tested it on that other pc and seems to be working fine.