Question motherboard doesn't light up but the pc seems to power on

[Rwr19]

So yesterday while i was on my computer, it randomly shut down, upon trying to turn it on again, the computer started, fans started spinning and everything lit up, but in a split of a second it shut down again. after a while the computer managed to boot up and was okay for maybe half an hour, but then shut down again with the same problem occuring.
I assumed my PSU (620w) has gone bad since it was pretty old, so i swapped it out for some corsair PSU (550w) from another computer. Now the PC seems to start up, the gpu light up, cpu, gpu and case fans start spinning, however the MB has like an orange lighting all around which wont light up anymore and i get a no signal from DP message on my monitor. I also tried plugging my mouse and keyboard into the MB and they seem to be getting no power.
I then tried pluggin the MB with the original PSU and it still wont light up. Is it possible i damaged the MB while swapping out the PSU? i had to take it out in order to get the PSU out.

My specs are:
Gigabyte RTX 3060TI
Ryzen 7 5800x
B550 aorus elite v2

 

[drivinfast247]

You didn't reuse any old power cables when you swapped the PSU?

 

[Rwr19]

You didn't reuse any old power cables when you swapped the PSU?

No, the replaced PSU has it's own cables.

 

[Rwr19]

So yesterday while i was on my computer, it randomly shut down, upon trying to turn it on again, the computer started, fans started spinning and everything lit up, but in a split of a second it shut down again. after a while the computer managed to boot up and was okay for maybe half an hour, but then shut down again with the same problem occuring.
I assumed my PSU (620w) has gone bad since it was pretty old, so i swapped it out for some corsair PSU (550w) from another computer. Now the PC seems to start up, the gpu light up, cpu, gpu and case fans start spinning, however the MB has like an orange lighting all around which wont light up anymore and i get a no signal from DP message on my monitor. I also tried plugging my mouse and keyboard into the MB and they seem to be getting no power.
I then tried pluggin the MB with the original PSU and it still wont light up. Is it possible i damaged the MB while swapping out the PSU? i had to take it out in order to get the PSU out.

My specs are:
Gigabyte RTX 3060TI
Ryzen 7 5800x
B550 aorus elite v2

Nevermind, the issue was due to my own stupidity, my ram got loose and putting it back in solved the issue