Question Pc wont boot

[Butterslime]

Hello friends, so a buddy of mine brought me his pc since its not booting into anything. I took a look at it and noticed the vga and boot fault lights stay on. I did the usual rounds and notices the gpu fans weren't spinning, tried it on my pc and nothing, I'm sure it's dead. I took a spare 750ti and 1050ti and put them in his pc and while the fans spin, the gpu fans spin and all his rgbs turn on I get no display. Could the mobo be dead? I keep getting the vga/boot faults. TIA and hope it makes sense. His specs are
Ryzen 2700x cpu I believe
Asrock b550 am gaming mobo
16gb ballistic ram
700w Thermaltake smart psu
Powercolor vga axrx 5600xt gpu

 

[kurdtnz]

Your friends B550 motherboard does not support 2000 series cpu's.

 

[Butterslime]

I gave up trying to tell him it wasn't compatible but he insisted, he swapped his 3600 that was originally there for that one when I'm assuming the gpu died. Ill have him bring me the original one. That's if it's even the 3600, God knows what he has at this point. Ill return in a few days. Thanks