I'm just facing this same issue since today after upgrading 20.04 kernel from 5.8.x to 5.12.6-051206-generic.
Second screen is detected by Nvidia, but black. When I change down the resolution from 1920x1080 to 1280x1024 the 2nd screen reappear. Then if I put back 1920x1080, the screen keeps alive but the refresh rate appears to 59hz in display settings, so screen is blinking. If I manually put the refresh rate to 60hz, the screen works fine until the next reboot. Then I have to start over. GPU is Nvidia GTX1060 and driver is Nouveau. Proprietary drivers didn't detects the 2nd screen at all. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1871721 Title: Second Monitor on HDMI blank screen/blink screen with Nvidia + Intel & Ubuntu 20.04? (ASUS Laptop) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1871721/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
