if that would be the case the last 2 moth since i switched to am5 and redid my whole setup would have not been possible 
but indeed deleting everything in /etc/NetworkManager/system-connections somehow solved the problem.
no i have to redo my whole setup but at least i have a working desktop again …
That was a shock i could have passed on XD
I really thought my motherboard was fried -.-
Thank you all for your support and fast responsetimes <3
it really helped alot calming me down.
One last question:
is there an even more stable stable branch?
Manjaro was the closest i could find to a gnomes based rolling release distro with a focus on stability.
If you want stable you should NOT use any rolling release…
Try debian/ubuntu for stability 
(I’m on Kubuntu / KDE)
I also have been irritated by :
raw-size: 681.22 GiB
size: 681.22 GiB (100.00%)
used: 264.19 GiB (38.8%)
fs: btrfs
But what seems to count is the part after used (38.8%)
To be really sure, please issue:
sudo btrfs filesystem usage /
This will show how healthy your btrfs is. 
Overall:
Device size: 681.22GiB
Device allocated: 270.02GiB
Device unallocated: 411.19GiB
Device missing: 0.00B
Device slack: 0.00B
Used: 267.32GiB
Free (estimated): 413.63GiB (min: 208.04GiB)
Free (statfs, df): 413.63GiB
Data ratio: 1.00
Metadata ratio: 2.00
Global reserve: 115.06MiB (used: 0.00B)
Multiple profiles: no
Data,single: Size:266.01GiB, Used:263.57GiB (99.08%)
/dev/nvme0n1p2 266.01GiB
Metadata,DUP: Size:2.00GiB, Used:1.87GiB (93.70%)
/dev/nvme0n1p2 4.00GiB
System,DUP: Size:8.00MiB, Used:48.00KiB (0.59%)
/dev/nvme0n1p2 16.00MiB
Unallocated:
/dev/nvme0n1p2 411.19GiB
regarding the rolling release = not stable i disagree.
but if some thing like that happens again even in manjaro i guess i really have to switch to fedora 
The rolling release thing was the last good thing windows 10 did. The only caveat was that you had to tick the “delay updates for 90 days” box to get the “stable branch”.
Sadly M$ has a lot of other problems (and subjectively cant compete with gnome xD)
I never said rolling releases are NOT stable, but they are, by nature, not as stable as the ones i mentioned…