Why does the desktop FPS drop significantly when using an NVIDIA graphics card compared to the AMD integrated graphics?
As mentioned, my laptop has hybrid graphics, with an NVIDIA 4060 GPU and an AMD 8845 CPU with integrated graphics. The system I am using is EndeavourOS with a KDE desktop on Wayland. The NVIDIA graphics driver is the latest version, 560. The refresh rate of the laptop’s built-in screen is 240Hz.
Clearly, the performance of the NVIDIA 4060 graphics card far exceeds that of the AMD integrated graphics. However, I am encountering the opposite situation on the KDE desktop.
When I disable the AMD integrated graphics and use only the NVIDIA card for the entire Linux system, the FPS on the KDE desktop drops significantly. Specifically, when the desktop is idle (e.g., no mouse movement for 5 seconds), the KDE desktop only runs at 120 FPS, roughly half of the maximum refresh rate. When I open a program, the desktop animations during program launch only reach around 210-220 FPS, far from the screen’s maximum refresh rate. Additionally, even before the animations finish, the FPS suddenly drops to around 160 FPS, giving the impression that opening a program is stuttering.
However, if I enable the integrated graphics for the Linux system, whether using both the AMD integrated graphics and the NVIDIA card simultaneously, or just enabling the AMD integrated graphics and disabling the NVIDIA card, this issue disappears. At the very least, there is no significant FPS fluctuation. Moreover, when the KDE desktop is idle for 5 seconds, the FPS stays at 240Hz.
What could be causing this problem? How can I resolve it?