Mouse cursor less smooth on 60Hz external monitors compared to Windows
I recently moved to using Kubuntu 26.04 after being on windows for quite a few years - it’s been fine but there’s something wrong with using the mouse on external monitor that is capped at 60hz as compared to my laptop screen which has a refresh rate of 240hz.
The cursor movement on my monitor feels laggy and not so smooth. On the laptop screen, the cursor is laggy when set to 60hz but when i change it to 120hz or 240hz the cursor feels smooth. The same behaviour is observed with the touchpad.
What I’ve done so far (with the help of an AI):
- Mouse polling rate confirmed active at ~1000Hz via libinput debug-events
- usbhid.mousepoll=1 kernel parameter applied and confirmed via /sys/module/usbhid/parameters/mousepoll
- Acceleration profile set to flat (PointerAccelerationProfile=1 in ~/.config/kcminputrc)
- Hardware cursor confirmed active — no software cursor fallback in journalctl
- KWin LatencyPolicy=Low set in ~/.config/kwinrc — no noticeable difference
- Cursor feels perfectly smooth on the laptop’s built-in 240Hz display, noticeably less smooth on 60Hz external monitors
Research suggests GNOME/Mutter handles hardware cursor plane initialisation more reliably than KWin on Wayland, resulting in better perceived cursor smoothness at 60Hz. Is this a known KWin limitation, and are there any KWin-specific settings or workarounds to improve cursor plane handling on external monitors connected via Thunderbolt dock?
Hardware info:
- Operating System: Kubuntu 26.04 LTS
- KDE Plasma Version: 6.6.4
- KDE Frameworks Version: 6.24.0
- Qt Version: 6.10.2
- Kernel Version: 7.0.0-15-generic (64-bit)
- Graphics Platform: Wayland
- Processors: 24 × Intel® Core™ Ultra 9 275HX
- Memory: 96 GiB of RAM (93.7 GiB usable)
- Graphics Processor 1: Intel® Graphics
- Graphics Processor 2: NVIDIA GeForce RTX 5060 Laptop GPU
- Docking station: Dell Thunderbolt 5 SD25TB5
- Monitor: Lenovo L32p-30 (60hz max)
I’ll appreciate any suggestions. Thanks.