If the screen is turning off before the 30-minute screen saver setting, the issue is usually the display power timeout, not the screen saver timeout. Screen saver and screen-off are separate settings.
Try this:
- Open Start > Settings > System > Power & battery > Screen, sleep, & hibernate timeouts.
- Change Turn my screen off after to a longer time for both:
- On battery
- When plugged in
- If needed, also increase Make my device sleep after so the PC does not sleep before the screen saver would start.
If the device is using Energy recommendations, Windows may also suggest shorter screen-off or sleep times:
- Open Start > Settings > System > Power & battery > Energy recommendations.
- Check whether settings such as Turn off my screen after 3 (or 10) minutes or Put my device to sleep after 3 (or 10) minutes were applied.
Important detail:
- The screen saver timeout controls when the screen saver starts after inactivity.
- The Turn my screen off after setting controls when the display goes black.
- If the display timeout is shorter than the screen saver timeout, the screen will turn off first.
References: