drivers - How to fix/diagnose GUI issues on Ubuntu 18.04/18.10?

For the past few weeks, there have been some issues with the GUI lately. I believe these issues started when I installed CUDA 9.0.

My machine:

• GPU: GeForce GTX 1060 Mobile + Intel HD Graphics


• OS: Ubuntu 18.10 Cosmic Cuttlefish

GUI Issues:

1. When switching to tty1 and logging in, the login screen's mouse
   cursor is still there (doesn't occur anymore)


2. Sometimes the, when I try to lock the screen, the display freezes on the Desktop and then a glitch occurs: the system menu keeps showing up multiple times on top of each other)


3. When I login, the screen flashes a couple of times and lags a bit
   before rendering the desktop (I believe this is because of a new TTY is starting up for X Server, although it doesn't happen when I switch to Intel Graphics from NVIDIA X Server Settings -> PRIME Profiles)


4. Sometimes when I logout and try to login, a "login loop" occurs where the I enter the password and the login screen keeps showing up instead of the desktop (I have to use chmod on .Xauthority to login)


5. When I lock the screen, and close the lid (suspend) then open it again, I find myself logged out.

At first I had Ubuntu 18.04 LTS, I thought if I upgraded to Ubuntu 18.10, these issues would be fixed but nothing happened.

Other things I tried:

1. Reinstalled the NVIDIA drivers


2. Uncommented WaylandEnable=false line in '/etc/gdm3/custom.conf'


3. Switched to LightDM (new issues occured so I switched back to GDM3)



4. Reinstalled GNOME and GDM3


5. Reinstalled X Server (using apt install --reinstall)

Is there any way to further diagnose/fix this problem? The only solution I'm thinking of is to install Ubuntu 16.04.