I can confirm this bug on Dell Precision 7680. System Configuration: - Laptop: Dell Precision 7680 - Ubuntu: 24.04 LTS - Desktop: Wayland (also tested on X11 - same issue) - GPU: Intel Raptor Lake-S UHD Graphics + NVIDIA RTX 3500 Ada Generation (hybrid) - Ports: Thunderbolt 4 USB-C
Symptoms: - Built-in HDMI port: Not detecting any monitors - USB-C to HDMI adapter: Not detecting any monitors - Both connections worked until recent kernel update (~2-3 weeks ago) - xrandr only shows eDP-1 (laptop screen), all other outputs show "disconnected" - dmesg shows no activity when plugging/unplugging monitors Tested Kernels (all BROKEN): - 6.14.0-24-generic: External monitors not detected - 6.14.0-32-generic: External monitors not detected - 6.14.0-34-generic: External monitors not detected - 6.14.0-35-generic: External monitors not detected What Works: - Same monitors and cables work fine with my home desktop PC - At work, monitors work via USB-C dock - Laptop screen (eDP-1) works perfectly Current kernel: 6.14.0-24-generic (reverted from 6.14.0-35) xrandr output shows only: eDP-1 connected primary 1920x1200 DP-1 disconnected HDMI-1 disconnected DP-2 disconnected DP-3 disconnected This appears to be a regression affecting the entire 6.14 kernel series on hybrid Intel+NVIDIA laptops. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2130288 Title: External monitor connected via usb-c is not detecting To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/2130288/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
