my need: the gpu work fine but i want gui to control things like brightness, refresh rate and other settings like in windows. importantly i fear system unstability from installing new things so i thought to ask experts here cause im extremely desire to control brightness and other settings through gui.
You could use ddcutil from the command line - that’s officially available for leap. (Vdu_controls is a wrapper for ddcutil, or optionally ddcutil-service, so it you install vdu_controls it would install ddcutil anyway).
Plasma-6 has brightness controls, and has recently added support for controlling the brightness of more than one monitor. But Plasma-6 isn’t yet officially available for Leap, and Plasma-6 is probably a bit less stable than Plasma-5 (depends a bit on how you use it).
Even if refresh rate controls are exposed, I’m not sure whether dynamically changing refresh rates is possible/advisable for X11, others might care to comment.
As you don’t tell what driver you are using…
After installation of the Nvidia drivers simply open nvidia-settings which is also available via the application starter menu as Nvidia X Server settings.
i installed nvidia settings but i didnt find option to control brightness which the main thing i look for. i want to change brightness with keyboard shortcut i already set one through shortcut settings but unable to change the brightness with it. i installed many widget but the same unable to change brightness.
That will depend on which desktop environment you use (KDE, GNOME, etc). But ddcutil can be used to control various things from the command-line, and you can probably bind a keyboard shortcut to the specific command you need, depending on the desktop envrionment.
Note that the nvidia-control panel only controls the output brightness range of the GPU card. It does not change the brightness of the connected monitor’s backlight.
This means that reducing the brightness via nvidia-settings reduces the steps of brightness, for example, the RGB values might be reduced to 0 to 180 instead of 0 and 255, as a result images will show a more limited color range.
A utility such as ddcutil uses VESA DDC Virtual-Control-Panel commands to tell the monitor to turn down it’s backlight, so the monitor still receives RBG 0…255. The Virtual-Control-Panel is equivalent to using the monitor’s built-in control panel. This approach should result in more faithful/richer representation of images (providing you don’t turn down the backlight too far).
If you’re not concerned about dynamic range, or perceiving shades of color, or picking out monsters in the gloom, then using the nvidia-settings (or even the command line xrandr) is an OK way to approach the problem.