Arch Linux

scaponch

Member

Registered: 2025-04-05

Posts: 1

When i connect a monitor to a laptop with nvidia gpu it lags

I have a Lenovo LOQ 15iax9e with Intel i5-12450HX and NVIDIA RTX 4050.
If I use only the laptop without an external monitor connected everything runs fine (I tried KDE, Gnome and Hyrpland) but when I connect an external monitor, the video in this screen is really laggy. Normally the framerate is fixed at 60 but if I do anything like resizing or moving windows, the framerate drops around 30-40 fps. I measured this with KDE but I have the same problem with Gnome and Hyrpland. Now I'm running 6.12.22-1-lts kernel but I have the same problem on the normal kernel.

I followed the Arch wiki to install Nvidia drivers.

• I'm using nvidia drivers because lspci -k -d ::03xx returns this:

  00:02.0 VGA compatible controller: Intel Corporation Alder Lake-S [UHD Graphics] (rev 0c)
          Subsystem: Lenovo Device 3d9e
          Kernel driver in use: i915
          Kernel modules: i915, xe
  01:00.0 VGA compatible controller: NVIDIA Corporation AD107M [GeForce RTX 4050 Max-Q / Mobile] (rev a1)
          Subsystem: Lenovo Device 3d9e
          Kernel driver in use: nvidia
          Kernel modules: nouveau, nvidia_drm, nvidia

• DRM is enabled 

• fbdev is enabled

• I tried to set these variables in ~/.config/environment.d/nvidia.conf

  __GL_SYNC_TO_VBLANK=1
  __GL_YIELD=USLEEP
  __GL_GSYNC_ALLOWED=0
  __GL_VRR_ALLOWED=0
  WLR_NO_HARDWARE_CURSORS=1

The only workaround i found to avoid this is to start an obs recording.

Last edited by scaponch (2025-04-10 15:01:07)