Quote:Would no NVidia driver in-use = no Plasma Desktop Effects?
No the nouveau driver should be able to provide OpenGL support.
To remove the nvidia driver use the driver manager to choose nouveau.
P.S.: Ok new idea. Before you try anything with the nividia -> nouveau thing try first switching the plymouth theme to something else. I guess the non readable text might be an issue of the default plymouth theme (having the colors set wrongly or problems on setting them with nvidia-kms).
So please run
Code:
sudo update-alternatives --config default.plymouth
Try doing that.
After that it is important to update the initramfs for the changes to also land in initrd.
So run [code]sudo update-initramfs -u[/b] aswell.
After that try restarting with a normal boot. You should see another bootsplash and hopefully some error message whith which we can analyze whats going wrong on your machine all the sudden.