@meiko60 why do you think that the reason for the freezes is the graphics driver. Isn't Linux completely freezing typically a running out of RAM (when you haven't set sufficient swap partitions or swap files). On KDE, you can enable the classical Ctrl+alt+del key to reset the xserver/Wayland (advanced keyboard options). Could you check whether this still works when the freeze occurs? Are there any special things in your system log?