Created attachment 188577 [details]
Power usage graph

SUMMARY

When playing doom ethernal, It works fine and gives me around 160+ FPS for like first 5 minutes after launching the game. Then, suddenly, performance drops to around ~50 FPS and the game becomes very stuttery.

I've tracked down the problem and it seems that dGPU (5060 laptop) is loosing power. I plotted GPU power usage in KDE System Monitor, and when I minimize the game, I see a jump in power usage. When I focus the game again, the power usage drops. Please see attached screenshot
This happens in all three modes - Windowed, Borderless Window and Fullscreen.

At around ~50W, I do get playable ~160FPS but when it drops to ~27W, I get ~50FPS and it becomes stuttery.

I think I have similar behavior in cs2 and dota2 as well.

The issue does not happens when laptop's internal is turned off. It also doesn't happen if I use internal display only and disconnect the monitor. Issue does not happen if If disable iGPU from bios

My external monitor is connected to iGPU and I'm not using reverse prime.

STEPS TO REPRODUCE
1. Connect external monitor to laptop with hybrid graphics. Make sure to connect monitor to iGPU and not dGPU
2. Start Doom Ethernal, CS2 or Dota2 (only tested with these) on external display
3.  Notice sudden drop power used by dGPU.
4. Switch to different window (alt+tab) and observe that GPU power usage is increased

I'm not sure if its KDE bug but since power to GPU is restored when window is not in focus makes me think that it has to do something window manager falsely reporting to window focus status to driver/game. If KDE devs can guide me more on how to debug this, that would be helpful as well


SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 6.5.4
KDE Frameworks Version: 6.22.0
Qt Version: 6.10.1
Kernel Version: 6.18.5-zen1-1-zen (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 250 w/ Radeon 780M Graphics
Memory: 72 GiB of RAM (66.6 GiB usable)
Graphics Processor 1: AMD Radeon 780M Graphics
Graphics Processor 2: NVIDIA GeForce RTX 5060 Laptop GPU
Manufacturer: LENOVO
Product Name: 83JG
System Version: LOQ 15AHP10

ADDITIONAL INFORMATION
Related post - https://bbs.archlinux.org/viewtopic.php?pid=2283264#p2283264