Hybrid mode: Plasma becomes sluggish after unplugging AC on ASUS TUF Gaming F15 FX507ZC4

### Pre-flight checklist

- [x] I have searched existing issues and this is not a duplicate.
- [x] I have read the [Contributing Guidelines](https://github.com/CachyOS/linux-cachyos/blob/master/CONTRIBUTING.md).
- [x] I have verified the issue is reproducible with the latest available CachyOS kernel.
- [ ] I have tried to reproduce the issue on Arch Linux's `linux` kernel.

### Upstream / vanilla kernel check

I have not tested with a vanilla/upstream kernel

### Kernel variant

linux-cachyos (EEVDF, Clang)

### System information (cachyos-bugreport.sh)

```text
https://paste.cachyos.org/p/2a90f44.log
```

### Manual system information (if cachyos-bugreport.sh is unavailable)

```text
Kernel

7.1.3-2-cachyos

CPU

Intel Core i5-12500H

GPU

Intel Iris Xe Graphics (i915)

NVIDIA GeForce RTX 3050 Laptop GPU
Driver: NVIDIA Open 610.43.03

Architecture

x86-64-v3
```

### Bug description

After booting while connected to AC power, KDE Plasma runs normally.

When the AC adapter is unplugged, within approximately one second Plasma/KWin becomes noticeably sluggish.

Examples include:

- Launcher animation
- Overview animation
- Window animations
- General desktop responsiveness

Plugging the charger back in does not restore responsiveness.

Only rebooting restores normal performance.

The issue is 100% reproducible.

The issue has been reproduced on:

[cachyos-bugreport.log](https://github.com/user-attachments/files/30112890/cachyos-bugreport.log)

It also occurs after multiple fresh CachyOS installations.

Note: I have not tested the upstream Arch linux kernel. I have only tested linux-cachyos and linux-cachyos-lts, where the issue is reproducible.

### Steps to reproduce

- Boot the laptop while connected to AC power.
- Log into KDE Plasma (Wayland).
- Confirm the desktop is smooth.
- Unplug the AC adapter.
- Within about one second, Plasma animations and responsiveness become noticeably sluggish.
- Plug the charger back in.
- The sluggishness remains.
- Reboot the system.
- Desktop responsiveness returns to normal.

### Expected behavior

Unplugging or reconnecting AC power should not affect Plasma responsiveness.

Desktop performance should remain smooth regardless of AC power state.

### Actual behavior

Immediately after unplugging AC power:

[dmesg-lag.txt](https://github.com/user-attachments/files/30112898/dmesg-lag.txt)

[journal-lag.txt](https://github.com/user-attachments/files/30112941/journal-lag.txt)

### Logs / stack traces

```text

```

### Additional system information

Desktop:
KDE Plasma 6.7.3
Wayland
KWin 6.7.3

Graphics mode:
Hybrid (supergfxctl)

supergfxctl:
5.2.7

Mesa:
26.1.5

NVIDIA Open Driver:
610.43.03

Additional observations during troubleshooting:

- Reproduced on multiple fresh CachyOS installations.
- Reproduced on both the latest CachyOS kernel and the CachyOS LTS kernel.
- Restarting kwin_wayland, PowerDevil, and nvidia-powerd did not resolve the issue.
- KWin continues using the Intel Iris Xe renderer before and after unplugging AC.
- glxinfo -B reports the same renderer before and after the issue occurs.
- CPU utilization remains mostly idle, but kwin_wayland CPU usage increases noticeably after unplugging AC.
- Memory usage remains normal.
- The issue appears to affect desktop compositing rather than application performance.

Related observation

In AsusMuxDgpu(called Ultimate mode in windows armoury crate in asus laptops) mode, I observe a different issue where Plasma becomes sluggish after the system has been idle for some time. Games continue to render normally, but desktop responsiveness degrades until reboot. This may or may not be related, but both issues involve graphics mode and power-state transitions on the same hardware.

before lag-
[dmesg-lag.txt](https://github.com/user-attachments/files/30112949/dmesg-lag.txt)
[journal-lag.txt](https://github.com/user-attachments/files/30112950/journal-lag.txt)
executed during lag-
[cachyos-bugreport.log](https://github.com/user-attachments/files/30112948/cachyos-bugreport.log)
[dmesg.txt](https://github.com/user-attachments/files/30112954/dmesg.txt)
[journal.txt](https://github.com/user-attachments/files/30112955/journal.txt)