Fresh install on a Thinkpad W530 with Ubuntu 20.04. The installation had no problem, but after rebooting, everything is extremely slow. When I unplug the monitor (DisplayPort) and use the internal screen, I have no problem.
I have checked the NVIDIA drivers and the problem is the same. I have also checked the BIOS settings and they make no change for Ubuntu.
However, Fedora 32 just worked with no problems. Windows 10 on the other hand couldn’t even use the external screen.
How can I solve this problem?