My PC crashes when I start a stream...

Hey guys! I have quiet a big issue and I wanted to contect the support but I can't remember my password and the password reset mail isn't arrivinge for 2 days now... I upgraded my PC, everything except the ssd's and I didn't reinstall Windows or so on because the change of the system worked flawlessly. I upgrade from a RTX 2060 Super to a RX 9070XT and now there is this issue. When I start a stream everything is fine, but when someone wants to look at my stream the problem starts, my stream doesn't load for them and for me the screen and the sound starts lagging. And sometimes I get to stop the stream and then everything is fine, but if not after some time my screen freezes permanently. And only a restart works. The funny part is, if I use discord web the stream works fine. I tried to deinstall Discord but it doesn't work... every time where I install it again it seems like I didn't delete everything because it logs me automatically in my account. I tried to delete Discord with Tools that can detect all Discord file but still the same, after 5 seconds of launching the install exe discord is open again with my Account logged in.

Can someone help me or provide me with some support? Sorry, English is not my Mother language!