No signal on display

Hello everyone,

Pc worked in the afternoon, then later it won't boot anymore. Reasons could be:
- turned off PSU switch while pc was still running
- brother has accidentally lightly hit the pc case

When turning on, no signal appears on the display, all fans rotate, mobo led's shine as they usually do and no beeping whatsoever.

First, I unplugged power cord, switched off PSU and pressed power button to free any left over electricity -> no signal.

Then, I removed CMOS battery for 15 minutes and put it back in -> no signal.

Then, I reduced my pc to the bare minimum of components required for POST and to see signal on the display: GPU, MOBO, one RAM, PSU with connections and CPU -> no signal.

Luckily, my brother has a very similar setup than mine, so I did a lot of troubleshooting by removing components off my system and testing it with my brothers system.

I did this with GPU, RAM and PSU -> all those components work with my brothers system.

I did also test the display and hdmi cable.

Could it possible be the CPU? I doubt it though. I think its more likely that the MOBO is down.

What would you recommend to me as the next steps? Ofcourse, if possible, I want to avoid testing the CPU in the other system as I don't have any heatfluid left.

System:
Asus B350-Plus
Ryzen 5 1600
Nvidia GTX 950
8gb Corsair RAM