Hybrid graphics broken after Nov 13 System76 kernel & NVIDIA update (HDMI signal loss in Hybrid mode)

[BuberryWorldwide]

After the System76/Pop!_OS update bundle on Nov 13, external HDMI output began flickering and dropping signal whenever the machine was set to Hybrid graphics mode. This behavior did not exist before the update.

The following updates were installed together (from /var/log/dpkg.log):

• linux-system76 → 6.17.4-76061704
• linux-image-generic and headers
• linux-firmware
• intel-microcode
• system76-power
• NVIDIA 580 open driver stack (580.82.09)

Immediately after rebooting, the external monitor would periodically go black and display “No HDMI Signal.” The blackout lasts about 1–2 seconds before returning. This repeats intermittently. Switching to Integrated (Intel-only) mode fixes the issue immediately.

Technical details:

In Hybrid mode:

• HDMI display loses signal randomly and recovers
• Monitor reports “No HDMI Signal”
• Signal loss happens even without touching the cable

This began immediately after the Nov 13 updates
Kernel logs show NVIDIA DRM mode setting failures:

nvidia-drm: No compatible format found
nvidia: Cannot find any crtc or sizes

These errors appear during boot while Hybrid mode is active.

Xorg provider list shows only one active provider:

Providers: number : 1
Provider 0: name:modesetting

This means Xorg is falling back to Intel-only mode even though Hybrid mode is enabled. At the same time, the NVIDIA driver still loads and produces errors in the background, which appears to cause display resets and HDMI signal drops.

Switching to Integrated mode using system76-power resolves the issue completely:

sudo system76-power graphics integrated

In Integrated mode:

• No HDMI flicker
• No signal loss
• No display resets

dmesg and journal logs stay clean

System information:

• Pop!_OS 22.04 LTS
• Kernel 6.17.4-76061704
• Intel Tiger Lake iGPU (i915)
• NVIDIA RTX 3050 Laptop GPU (GA107-A)
• HDMI output is wired to iGPU
• NVIDIA driver version 580.82.09 (open kernel)

system76-power was set to Hybrid during the issue

Issue disappears entirely in Integrated mode

Expected behavior:
Hybrid mode should allow Intel to drive the display while NVIDIA remains available for offloading, without causing HDMI link resets or output flickering.

Actual behavior:
Hybrid mode leads to repeated HDMI signal drops and display pipeline resets when using kernel 6.17.4 with NVIDIA 580.

Workaround:
Switching to Integrated mode resolves the problem for now.

I can provide full logs (journalctl, dmesg, Xorg logs, system76-power output) if needed.