Did you try installing the nvidia driver?
Please try: sudo apt install nvidia-driver-390 and then reboot.
If you still have problems after that then please also run: dpkg -l > dpkgl.txt and send us the resulting dpkgl.txt file.
Did you try installing the nvidia driver?
Please try:
sudo apt install nvidia-driver-390
and then reboot.
If you still have problems after that then please also run:
dpkg -l > dpkgl.txt
and send us the resulting dpkgl.txt file.