Long time Fedora user, since RH8.

I upgraded my main workstation from F21 to F22.  F21 was totally stable and great.  F22 has been nothing but trouble.

The main issue I have is session freezing that appears to happen right before the KDE (Plasma) desktop is displayed.  I have this problem with both nVidia and nouveau drivers.

The kernel seems to run fine.  I can ctrl alt F3 and start a console session and it runs fine.  But I can't get a KDE (Plasma) session to run at all.

How do I troubleshoot this ?