cosmic-comp hangs at boot with exactly one external monitor connected (hybrid Intel/NVIDIA, Gaze15)

[Adrianm6254]

System Information

• Hardware: System76 Gaze15 (gaze15)
• OS: Pop!_OS 24.04 LTS (COSMIC)
• Kernel: 7.0.11-76070011-generic
• GPUs: Intel (Cometlake, device ID 9bc4) + NVIDIA GeForce GTX 1650 Ti
• Graphics mode: hybrid (on-demand)
• External displays: one via HDMI (Intel iGPU, card1-HDMI-A-1), one via DP

Issue Description

cosmic-greeter/cosmic-comp reliably hangs at boot (blank screen, cursor visible in top-left, no login UI ever appears) when exactly one external monitor is connected at power-on. This is consistent and reproducible:

• 0 external monitors connected at boot → boots fine to login screen
• 2 external monitors connected at boot (one HDMI, one DP) → boots fine to login screen
• Exactly 1 external monitor connected at boot (either the HDMI or the DP one, tested individually) → hangs indefinitely at blank screen with only a cursor

Once booted successfully (0 or 2 monitors), hot-plugging monitors afterward works correctly in either direction.

Relevant Log Output

systemctl status cosmic-greeter during the hang shows the service as active (running) with cosmic-comp alive (state S/sleeping, not crashed), holding the NVIDIA GPU per nvidia-smi (6MiB, 0% util). No panic or error is logged during the hang itself — journalctl for the unit shows only the routine:

pam_unix(cosmic-greeter:session): session opened for user cosmic-greeter
gkr-pam: couldn't unlock the login keyring.
cosmic-comp: shortcuts custom config error: GetKey("custom", ... NotFound)
cosmic-comp: error loading system dark theme

DRM connector status during a single-external-monitor hang:

card0-DP-1 (nvidia): disconnected
card1-eDP-1 (intel, internal): connected
card1-HDMI-A-1 (intel, external): connected

After an extended hang (~6+ minutes) on one boot, the greeter eventually exited and the service crash-looped 5 times rapidly (check_children: greeter exited without creating a session) before hitting systemd's start-limit, suggesting some downstream state corruption once the initial hang times out.

Expected Behavior

cosmic-comp should initialize successfully and reach the login screen when exactly one external monitor is connected at boot, matching the working behavior when 0 or 2 are connected.

Additional Context

This may be related to:

• NVIDIA graphics meta-issue cosmic-epoch#168 (NVIDIA meta-issue), which references cosmic-comp#243 — "external Nvidia monitors sometimes don't work at start (gaze15 GTX 1650)" — same hardware model.
• [Display] Internal laptop screen stuck on vendor logo when booting with external monitor (Single Display Mode) cosmic-epoch#2933 — similar single-external-monitor boot hang on different hardware, where analysis found "Unable to become drm master, assuming unprivileged mode."

Happy to provide additional logs (full journalctl, sudo dmesg, strace output) on request.

[Xujan24]

Hi there,
I am also experiencing similar issue. I have a single monitor setup and the login screen doesn't show up; however, when I connect the external montior after login (or when the login screen shows up in the laptop screen), it works fine. And I've tried both 'hybrid' and 'nvidia' graphics options. I don't have a dual external monitor setup to test if it works.

SYSTEM INFO:

Laptop: Razer Blade 15 Base (Early 2020)
OS: Pop!_OS 24.04 LTS x86_64
Kernel: Linux 7.0.11-76070011-generic
DE: COSMIC 1.0.0
WM: cosmic-comp (Wayland)
GPU 1: NVIDIA GeForce RTX 2060 Mobile (v: 580.173.02) + Intel UHD Graphics @ 1.15 GHz

[Xujan24]

With the latest updates, it seems to have been fixed for me. Now, the login screen appears in both the built-in display and the external monitor.